Reference

Submodules

pyexphys.cardio module

pyexphys.cardio.cardiac module

The cardiac module is a collection of heart-related equations used in health assessments, and calculating heart rate training zones.

class pyexphys.cardio.cardiac.Astrand

Bases: pyexphys.cardio.cardiac.HREstimator

The Astrand equation for estimating maximum heart rate (HRMax). For use on men and women ages 4 to 34 yr

Astrand (1952)

age(hr)

Parameters:hr (float) – max heart rate, given in beats/minute Returns:age, given in years Return type:float

predict(age)

Parameters:age (float) – given in years Returns:max heart rate, given in beats/minute Return type:float

class pyexphys.cardio.cardiac.Gellish

Bases: pyexphys.cardio.cardiac.HREstimator

The Gellish equation for estimating maximum heart rate (HRMax). For use on men and women participants in an adult fitness program with broad range of age and fitness levels

Gellish (2007)

Farazdaghi GR, Wohlfart B (November 2001). “Reference values for the physical work capacity on a bicycle ergometer for women between 20 and 80 years of age”. site Clin Physiol. 21 (6): 682u20147. doi:10.1046/j.1365-2281.2001.00373.x. PMID 11722475.

Wohlfart B, Farazdaghi GR (May 2003). “Reference values for the physical work capacity on a bicycle ergometer for men – a comparison with a previous study on women”. site Clin Physiol Funct Imaging. 23 (3): 166u201470. doi:10.1046/j.1475-097X.2003.00491.x. PMID 12752560.

age(hr)

Parameters:hr (float) – max heart rate, given in beats/minute Returns:age, given in years Return type:float

predict(age)

Parameters:age (float) – given in years Returns:max heart rate, given in beats/minute Return type:float

class pyexphys.cardio.cardiac.Gulati

Bases: pyexphys.cardio.cardiac.HREstimator

The Gulati equation for estimating maximum heart rate (HRMax). For use on asymptomatic middle aged women referred for stress testing

Gulati (2010)

Gulati M, Shaw LJ, Thisted RA, Black HR, Bairey Merz CN, Arnsdorf MF (2010). “Heart rate response to exercise stress testing in asymptomatic women: the st. James women take heart project”. Circulation. 122 (2): 130u20147. doi:10.1161/CIRCULATIONAHA.110.939249. PMID 20585008.

age(hr)

Parameters:hr (float) – max heart rate, given in beats/minute Returns:age, given in years Return type:float

predict(age)

Parameters:age (float) – given in years Returns:max heart rate, given in beats/minute Return type:float

class pyexphys.cardio.cardiac.HF

Bases: pyexphys.cardio.cardiac.HREstimator

The Haskell & Fox equation for estimating maximum heart rate (HRMax). Recommended for use with older adults. Fox (1971)

age(hr)

Parameters:hr (float) – max heart rate, given in beats/minute Returns:age, given in years Return type:float

predict(age)

Parameters:age (float) – given in years Returns:max heart rate, given in beats/minute Return type:float

class pyexphys.cardio.cardiac.HREstimator

Bases: object

Estimator classes for predicting maximum heart rate (HRMax) based on age. All of these classes implement the Estimator interface. To change the equation for predicting HRMax, developers can swap out the estimator class rather than changing their application logic.

class pyexphys.cardio.cardiac.LM

Bases: pyexphys.cardio.cardiac.HREstimator

Nes, B. M., et al. “Age-predicted maximal heart rate in healthy subjects: The HUNT Fitness Study.” Scandinavian journal of medicine & science in sports 23.6 (2013): 697-704

age(hr)

Parameters:hr (float) – max heart rate, given in beats/minute Returns:age, given in years Return type:float

predict(age)

Parameters:age (float) – given in years Returns:max heart rate, given in beats/minute Return type:float

class pyexphys.cardio.cardiac.Miller

Bases: pyexphys.cardio.cardiac.HREstimator

age(hr)

Parameters:hr (float) – max heart rate, given in beats/minute Returns:age, given in years Return type:float

predict(age)

Parameters:age (float) – given in years Returns:max heart rate, given in beats/minute Return type:float

class pyexphys.cardio.cardiac.Nes

Bases: pyexphys.cardio.cardiac.HREstimator

age(hr)

Parameters:hr (float) – max heart rate, given in beats/minute Returns:age, given in years Return type:float

predict(age)

Parameters:age (float) – given in years Returns:max heart rate, given in beats/minute Return type:float

class pyexphys.cardio.cardiac.OaklandL

Bases: pyexphys.cardio.cardiac.HREstimator

age(hr)

Parameters:hr (float) – max heart rate, given in beats/minute Returns:age, given in years Return type:float

predict(age)

Parameters:age (float) – given in years Returns:max heart rate, given in beats/minute Return type:float

class pyexphys.cardio.cardiac.OaklandNL1

Bases: pyexphys.cardio.cardiac.HREstimator

age(hr)

Parameters:hr (float) – max heart rate, given in beats/minute Returns:age, given in years Return type:float

predict(age)

Parameters:age (float) – given in years Returns:max heart rate, given in beats/minute Return type:float

class pyexphys.cardio.cardiac.OaklandNL2

Bases: pyexphys.cardio.cardiac.HREstimator

age(hr)

Parameters:hr (float) – max heart rate, given in beats/minute Returns:age, given in years Return type:float

predict(age)

Parameters:age (float) – given in years Returns:max heart rate, given in beats/minute Return type:float

class pyexphys.cardio.cardiac.RL

Bases: pyexphys.cardio.cardiac.HREstimator

Robergs R, Landwehr R (2002). “The Surprising History of the ‘HRmax=220-age’ Equation” (PDF). Journal of Exercise Physiology. 5 (2): 1u201410.

age(hr)

Parameters:hr (float) – max heart rate, given in beats/minute Returns:age, given in years Return type:float

predict(age)

Parameters:age (float) – given in years Returns:max heart rate, given in beats/minute Return type:float

class pyexphys.cardio.cardiac.TMS

Bases: pyexphys.cardio.cardiac.HREstimator

The Tanaka equation for estimating maximum heart rate (HRMax). For use on healthy men and women

Tanaka H, Monahan KD, Seals DR (January 2001). “Age-predicted maximal heart rate revisited”. site J. Am. Coll. Cardiol. 37 (1): 153u20146. doi:10.1016/S0735-1097(00)01054-8. PMID 11153730.

age(hr)

Parameters:hr (float) – max heart rate, given in beats/minute Returns:age, given in years Return type:float

predict(age)

Parameters:age (float) – given in years Returns:max heart rate, given in beats/minute Return type:float

pyexphys.cardio.cardiac.karvonen(intensity, rest, maximum)

The Karvonen Method for target heart rate (THR) - using a range of 50% to 85% intensity. The formula is used to calculate heart rate for exercise at a percentage training intensity.

Parameters:

• intensity (float) – given as a decimal between 0 and 1
• rest (float) – resting heart rate, given in beats/minute
• maximum (float) – maximum heart rate, given in beats/minute

Returns:

heart rate for exercise at the given intensity, given in beats/minute

Return type:

float

pyexphys.cardio.cardiac.mean_arterial_pressure(diastolic_bp, systolic_bp)

The Karvonen Method for target heart rate (THR) - using a range of 50% to 85% intensity. The formula is used to calculate heart rate for exercise at a percentage training intensity.

Parameters:

• intensity (float) – given as a decimal between 0 and 1
• rest (float) – resting heart rate, given in beats/minute
• maximum (float) – maximum heart rate, given in beats/minute

Returns:

heart rate for exercise at the given intensity, given in beats/minute

Return type:

float

pyexphys.cardio.cardiac.zoladz(hrMax, adjuster)

Zoladz Method for target heart rate (THR) - derives exercise zones by subtracting values from HRmax. Results are +/- 5 bpm - Zone 1 Adjuster (easy exercise) = 50 bpm - Zone 2 Adjuster = 40 bpm - Zone 3 Adjuster = 30 bpm - Zone 4 Adjuster = 20 bpm - Zone 5 Adjuster (extremely tough exercise) = 10 bpm

pyexphys.cardio.energy module

The energy module calculates the energy requirements of the human body to maintain stability. These values, such as Basal Metabolic Rate (BMR), Estimated Energy Requirement (EER) are used in estimating the required kilocalories (kcal) required by the human body based on activity level. This value is important in developing lifestyle-based nutrition plans.

class pyexphys.cardio.energy.AdultTEE(gender, pal)

Bases: pyexphys.cardio.energy.TEEEstimator

predict(age, weight, height)

Parameters:

• age (float) – The age of a person, given in years
• weight (float) – Body weight, given in kilograms
• height (float) – Body height, given in meters

Returns:

total energy expenditure, given in kilocalories/day

Return type:

float

class pyexphys.cardio.energy.BMREstimator(gender)

Bases: object

A class for estimating the basal metabolic rate of children, adults, and older adults over a given time period.

__init__(gender)

Parameters:gender (pyexphys.enums.Gender) – Gender of the individual

class pyexphys.cardio.energy.ChildTEE(gender, pal)

Bases: pyexphys.cardio.energy.TEEEstimator

predict(age, weight, height)

Parameters:

• age (float) – The age of a person, given in years
• weight (float) – Body weight, given in kilograms
• height (float) – Body height, given in meters

Returns:

total energy expenditure, given in kilocalories/day

Return type:

float

class pyexphys.cardio.energy.HB(gender)

Bases: pyexphys.cardio.energy.BMREstimator

The original Harris-Benedict Equation for basal metabolic rate.

Harris J, Benedict F (1918). “A Biometric Study of Human Basal Metabolism”. PNAS. 4 (12): 370u20143. Bibcode:1918PNAS….4..370H. doi:10.1073/pnas.4.12.370. PMC 1091498Freely accessible. PMID 16576330. Article PDF

predict(age, weight, height)

Parameters:

• age (float) – age, given in years
• weight (float) – body weight, given in kilograms
• height (float) – body height, given in meters

Returns:

basal metabolic rate, given as kilocalories/day

Return type:

float

class pyexphys.cardio.energy.MSJ(gender)

Bases: pyexphys.cardio.energy.BMREstimator

The Mifflin St. Jeor Equation for basal metabolic rate (BMR). The American Dietetic Association (2003) recommends using this equation over Harris-Benedict to estimate RMR in healthy individuals.

Mifflin, MD; St Jeor, ST; Hill, LA; Scott, BJ; Daugherty, SA; Koh, YO (1990). “A new predictive equation for resting energy expenditure in healthy individuals”. The American Journal of Clinical Nutrition. 51 (2): 241u20147. PMID 2305711.

predict(age, weight, height)

Parameters:

• age (float) – age, given in years
• weight (float) – body weight, given in kilograms
• height (float) – body height, given in meters

Returns:

basal metabolic rate, given as kilocalories/day

Return type:

float

class pyexphys.cardio.energy.RevisedHB(gender)

Bases: pyexphys.cardio.energy.BMREstimator

The Revised Harris-Benedict Equation for basal metabolic rate (BMR). Accurately estimates the REE of normal-weight, overweight, and obese individuals but overestimate REE in underweight individuals.

Roza, Allan M; Shizgal, Harry M (1984). “The Harris Benedict equation reevaluated: resting energy requirements and the body cell mass”. The American Journal of Clinical Nutrition. 40: 168u2014182.

predict(age, weight, height)

Parameters:

• age (float) – age, given in years
• weight (float) – body weight, given in kilograms
• height (float) – body height, given in meters

Returns:

basal metabolic rate, given as kilocalories/day

Return type:

float

class pyexphys.cardio.energy.TEEEstimator(gender, pal)

Bases: object

A class for estimating the total energy expenditure (TEE) in individuals of varying levels of physical activity.

__init__(gender, pal)

Parameters:

• gender (pyexphys.enums.Gender) – The gender of an individual
• pal (pyexphys.enums.PAL) – The physical activity level of an individual

fromActivity(weight, mets)

Humphrey R, The Exercise Caloric Challenge, Clinical Applications, ACSMu0027s Health & Fitness Journal, March/April 2006, Vol. 10, No. 2 pp.40-41

Parameters:

• weight (float) – body weight, given in kilograms
• mets (float) – METs, given in kcal/kg/hour

Returns:

kcal/min

Return type:

float

class pyexphys.cardio.energy.Terrain(weight, speed, load)

Formulas for calculating energy expenditure

pandolf(terrain, slope)

The Pandolf, Givoni, and Goldman formula for calculating energy expenditure. Funded by the United States Army Research Institute of Environmental Medicine.

Pandolf K.B., Givoni B., Goldman R.F. Predicting energy expenditure with loads while standing or walking very slowly. J Appl Physiol 43: 577u2014581, 1977

Parameters:

• terrain (int) –
• slope (float) – slope of the terrain, given as a percentage

Returns:

metabolic rate, given in Watts

Return type:

float

santee(terrain, slope)

The Santee formula for calculating energy expenditure. The formula is an updated version of the Pandolf formula that more accurately takes into account downhill travel. The formula is for use with negative (downhill) slopes.

Matthew W.T., Santee W.R., Berglund L.G. Solar Load Inputs for USARIEM Thermal Strain Models and the Solar Radiation-Sensitive Components of the WBGT Index (Technical Report T01/13u2014 01). Natick, MA: U.S. Army Research Institute of Environmental Medicine, 2001.

Parameters:

• terrain (int) –
• slope (float) – slope of the terrain, given as a percentage

Returns:

metabolic rate, given in Watts

Return type:

float

pyexphys.cardio.energy.cunningham(lbm)

The Cunningham equation for resting metabolic rate (RMR). This formula is similar to Katch-McArdle, but provides a slightly higher estimate.

pyexphys.cardio.energy.kma(lbm)

The Katch-McArdle Formula for resting daily energy expenditure (RDEE). This formula takes lean body mass/fat-free mass (in kilograms) as the only argument.

McArdle, W (2006). Essentials of Exercise Physiology. Lippincott Williams & Wilkins. p. 266. ISBN 9780495014836.

pyexphys.cardio.respiration module

The respiration module contains formulas for estimating the capacity of the lungs and for estimating the efficiency of the respiration system using VO2/VO2Max. These equations are used in general health assessments, aerobic performance assessments, and in developing training plans for endurance sports.

class pyexphys.cardio.respiration.ResidualVolume(gender, age, weight, height)

Bases: object

A class for calculating the residual volume of the lungs for men and women across the lifespan.

__init__(gender, age, weight, height)

Parameters:

• gender (pyexphys.enums.Gender) – The gender of an individual
• age (float) – The age of a person, given in years
• weight (float) – Body weight, given in kilograms
• height (float) – Body height, given in meters

berglund()

Berglund, E., Birath, G., Bjure, J., Grimby, G., Kjellmar, I., Sandvist, L., and Soderholm, B. 1963. Spirometric studies in normal subjects. I. Forced expirograms in subjects between 7 and 70 years of age. Acta Medica Scandinavica 173: 185-192.

Returns:residual volume, given in liters Return type:float

black()

Standard Error of the Estimate (SEE) = 0.46 Liters

Black, L.F., Offord, K., and Hyatt, R.E. 1974. Variability in the maximum expiratory flow volume curve in asymptomatic smokers and nonsmokers. American Review of Respiratory Diseases 110: 282-292.

Returns:residual volume, given in liters Return type:float

boren()

Standard Error of the Estimate (SEE) = 0.53

Boren, H.G., Kory, R.C., and Syner, J.C. 1966. The Veteran’s Administration-Army cooperative study of pulmonary functionsL II. The lung volume and its subdivisions in normal men. American Journal of Medicine 41: 96-114.

Returns:residual volume, given in liters Return type:float

goldman()

Goldman, H.I., and Becklake, M.R. 1959. Respiratory function tests: Normal values at medium altitudes and the prediction of normal results. American Review of Tuberculosis and Respiratory Diseases 79: 457-467.

Returns:residual volume, given in liters Return type:float

obrien(bsa)

Standard Error of the Estimate (SEE) = 0.49 Liters

O’Brien, R.J., and Drizd, T.A. 1983. Roentgenographic determination of total lung capacity: Normal values from a national population survey. American Review of Respiratory Diseases 128: 949-952.

Returns:residual volume, given in liters Return type:float

class pyexphys.cardio.respiration.VO2(gender, age, weight, height)

Bases: object

A class for calculating VO2 and VO2Max

arm_ergometry_gross(mass, work)

Heyward, Vivian H. “Metabolic Equations for Estimating Gross VO2 (ACSM 2010).” 2010. Advanced Fitness Assessment and Exercise Prescription. 6th ed. Champaign, IL: Human Kinetics, 2010. N. pag. Print.

Ehrman, Jonathan K. ACSM’s Resource Manual for Guidelines for Exercise Testing and Prescription. 6th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins, 2010. Print.

Parameters:

• mass (float) – given in kilograms
• work (float) – given in Watts

Returns:

VO2Max, given in mL/kg/min

Return type:

float

astrand_step(hr)

The Astrand Step Test formula for estimating a participant’s VO2Max.

Marley, W. P., and A. C. Linnerud. “Astrand-ryhming Step Test Norms for College Students.” British Journal of Sports Medicine 10.2 (1976): 76-79. NIH. Web. 5 Nov. 2016. <http://bjsm.bmj.com/content/10/2/76.long>.

Parameters:hr (float) – given in beats/minute Returns:VO2Max, given in L/min Return type:float

balke(time)

Balke and Ware (1959) exercise test protocols.

Source (Men) Pollock, M.L., Bohannon, R.L., Cooper, K.H., Ayres, J.J., Ward, A., White, S.R., and Linnerud, A.C. 1976 A comparative analysis of four protocols for maximal treadmill strss testing. American Heart Journal 92: 39-46.

Source (Women) POLLOCK et al. (1982) Comparative analysis of physiologic responses to three different maximal graded exercise test protocols in healthy women. American Heart Journal, 103 (3), p. 363-373

Parameters:distance (float) – distance traversed during the test, given in meters Returns:VO2Max, given in mL/kg/min Return type:float

balke_15min_run(distance)

The Balke formula for the 15 min run test for VO2Max.

Parameters:distance (float) – distance traversed during the test, given in meters Returns:VO2Max, given in mL/kg/min Return type:float

bruce_ec(time)

A VO2Max prediction equation for use with cardiac patients and elderly patients when using the Bruce Treadmill protocol.

Standard Error of Estimation: 4.9 mL/kg/min

Note: Used only for treadmill walking while holding the handrails

McConnell, Timothy R.;Clark, Bernard A., “Prediction of Maximal Oxygen Consumption During Handrail-Supported Treadmill Exercise”. Journal Of Cardiopulmonary Rehabilitation And Prevention, 1987

Parameters:time (float) – given in minutes Returns:VO2Max, given in mL/kg/min Return type:float

bruce_female(time)

The Bruce protocol equation for use with active and sedentary women. The Bruce protocol is used for estimating VO2Max based on multi-stage treadmill exercise. The protocol increases the workload by changing both speed and grade of the treadmill.

Note: For use with the standard Bruce protocol, not the Modified Bruce protocol

Standard Error of Estimate: 2.7 mL/kg/min

POLLOCK et al. (1982) Comparative analysis of physiologic responses to three different maximal graded exercise test protocols in healthy women. American Heart Journal, 103 (3), p. 363-373

Parameters:time (float) – given in minutes Returns:VO2Max, given in mL/kg/min Return type:float

bruce_male(time, time2, time3)

The Bruce protocol equation for use with active and sedentary men. The Bruce protocol is used for estimating VO2Max based on treadmill exercise.

Standard Error of Estimate: 3.35 mL/kg/min

Note: For use with the standard Bruce protocol, not the Modified Bruce protocol

FOSTER et al. (1984) Generalized equations for predicting functional capacity from treadmill performance. American Heart Journal, 107 (6), p. 1229-1234

Parameters:

• time (float) – given in minutes
• time2 (float) – given in minutes
• time3 (float) – given in minutes

Returns:

VO2Max, given in mL/kg/min

Return type:

float

cooper(distance)

The Cooper VO2Max test is a submaximal VO2Max test based on a population of healthy adults. Returns VO2Max in mL/kg*min.

COOPER, K.H. (1968) A means of assessing maximal oxygen intake. JAMA. 203, p. 135-138

Parameters:distance (float) – given in miles Returns:VO2Max, given in mL/kg*min Return type:float

cureton_child(time)

The Cureton formula for estimating VO2Peak in the 1.0 mile run/walk in children (8-17 years old).

Cureton, K.J., Sloniger, M., O’Bannon, J., Black, D., and McCormack, W. 1995. A generalized equation for prediction of VO2peak from 1-mile run/walk performance. Medicine & Science in Sports & Exercise 27: 445-451.

Note: For evaluating the fitness of younger children (5-7 years old), the 0.5 mile run/walk test is recommended.

Rikli, Roberta E., Clayre Petray, and Ted A. Baumgartner. “The Reliability of Distance Run Tests for Children in Grades K-4.” Research Quarterly for Exercise and Sport 63.3 (1992): 270-76. NCBI. Web. 10 Nov. 2016. <https://www.ncbi.nlm.nih.gov/pubmed/1513957>.

Parameters:distance (float) – distance traversed during the test, given in meters Returns:VO2Max, given in mL/kg/min Return type:float

ebbeling_treadmill(speed, hr)

A single-stage treadmill walking test developed by Ebbeling and colleagues for estimating VO2max of low-risk, healthy adults 20-59 years.

Ebbeling, Cara B., Ann Ward, Elaine M. Puleo, Jeffrey Widrick, and James M. Rippe. “Development of a Single-stage Submaximal Treadmill Walking Test.” Medicine & Science in Sports & Exercise 23.8 (1991): n. pag. NIH. Web. 5 Nov. 2016. https://www.ncbi.nlm.nih.gov/pubmed/1956273.

Parameters:

• speed (float) – given in miles/hour
• hr (float) – given in beats/minute

Returns:

VO2Max, given in mL/kg/min

Return type:

float

fox_ergometry(hr5)

The equation for predicting VO2Max in a population of healthy adults using the sub-maximal Fox test.

Fox, E. L. 1973. A simple, accurate technique for predicting maximal aerobic power. Journal of Applied Physiology, 35: 914 - 16

Parameters:hr5 (float) – heart rate after 5 minutes of cycling, given in beats/minute Returns:VO2Max, given in mL/kg/min Return type:float

george_rw(time)

The formula for the George single-stage jogging test formula. For use with the George 1 mile jog test.

George, J., Vehrs, P., Allsen, P., Fellingham, G., and Fisher, G. 1993. VO2max estimation from a sub-maximal 1-mile track jog for fit college-age individuals. Medicine & Science in Sports & Exercise 25: 401-406

Parameters:time (float) – given in minutes Returns:VO2Max, given in mL/kg/min Return type:float

george_steady(time, hr)

The George formula for the 1 mile steady state jog test. Returns VO2Max in mL/kg/min.

George, J., Vehrs, P., Allsen, P., Fellingham, G., and Fisher, G. 1993. VO2max estimation from a sub-maximal 1-mile track jog for fit college-age individuals. Medicine & Science in Sports & Exercise 25: 401-406

Parameters:

• speed (float) – given in miles/hour
• hr (float) – heart rate in beats/minute

Returns:

VO2Max, given in mL/kg/min

Return type:

float

george_treadmill(speed, hr)

George, J., Vehrs, P., Allsen, P., Fellingham, G., and Fisher, G. 1993. VO2max estimation from a sub-maximal 1-mile track jog for fit college-age individuals. Medicine & Science in Sports & Exercise 25: 401-406

Parameters:

• speed (float) – given in miles/hour
• hr (float) – heart rate in beats/minute

Returns:

VO2Max, given in mL/kg/min

Return type:

float

gilbert_daniels(velocity, time)

The Glibert-Daniels formula for VO2Max. This formula is used to calculate VO2Max from race results.

DANIELS, J. (2005) Daniels Running Formula. 2nd Ed. Leeds, UK: Human Kinetics. p. 48

Parameters:

• velocity (float) – given in meters/minute
• time (float) – given in minutes

Returns:

VO2Max, given in mL/kg/min

Return type:

float

kline(time, hrPeak)

The Kline et al. (1987) formula for the 1-mile walk Rockport Test for VO2Max.

Kline, Greg M., John P. Porcari, Robert Hintermeister, Patty S. Freedson, Ann Ward, Robert F. Mccarron, Jessica Ross, and James M. Rippe. “Estimation of &OV0312;O2max from a One-mile Track Walk, Gender, dob, and Body Weight.” Medicine & Science in Sports & Exercise 19.3 (1987): n. pag. Web.

McSwegin P, Plowman S, Wolff G, Guttenberg G. The validity of a one-mile walk test for high school age individuals. Measurement in Physical Education and Exercise Science 1998;2:47-63.

George, J. D. et al. VO2max estimation from a submaximal 1-mile track jog for fit college-age individuals. Medicine and Science in Sports and Exercise, 25, 401-406, 1993.

Parameters:

• time (float) – given in minutes
• hrPeak (float) – given in beats/minute

Returns:

VO2Max, given in mL/kg/min

Return type:

float

larsen(time, hr)

The Larsen VO2Max formula for use in the 1.5 mile run/walk test. For use with young adults (18-29 years old).

Standard Error of Estimation = 2.5 mL/kgmin TE = 2.68 mL/kg*min

LARSEN, G. et al. (2002) Prediction of maximum oxygen consumption from walking, jogging, or running. Research quarterly for exercise and sport, 73 (1), p. 66-72.

Parameters:

• time (float) – given in minutes
• hr (float) – given in beats/minute

Returns:

VO2Max, given in mL/kg * min

Return type:

float

leg_ergometry_gross(mass, work)

Heyward, Vivian H. “Metabolic Equations for Estimating Gross VO2 (ACSM 2010).” 2010. Advanced Fitness Assessment and Exercise Prescription. 6th ed. Champaign, IL: Human Kinetics, 2010. N. pag. Print.

Parameters:

• mass (float) – given in kilograms
• work (float) – given in Watts

Returns:

VO2Max, given in mL/kg/min

Return type:

float

leger(speed)

A 20m Shuttle run test developed by Leger and colleagues (1988) to test the aerobic fitness of children, dobs 8-19 years

Leger, L. A., D. Mercier, C. Gadoury, and J. Lambert. “The Multistage 20 Metre Shuttle Run Test for Aerobic Fitness.” Journal of Sports Sciences 6.2 (1988): 93-101. NCBI. Web. 10 Nov. 2016. <https://www.ncbi.nlm.nih.gov/pubmed/3184250>.

Parameters:velocity (float) – given in km/hour Returns:VO2Max, given in mL/kg/min Return type:float

qc_step(hr)

The Queen’s College Step Test formula for estimating a participant’s VO2Max.

McArdle, W.D., Katch, F.I., Pechar, G.S., Jacobson, L., and Ruck, S. 1972. Reliability and interrelationships between maximal oxygen intake, physical working capacity and step-test scores in college women. Medicine and Science in Sports 4: 182-186.

Parameters:hr (float) – given in beats/minute Returns:VO2Max, given in mL/kg/min Return type:float

reserve(vo2Max, vo2Rest=3.5)

VO2 Reserve (VO2R) is the difference between resting VO2 and VO2Max. Percent VO2 Reserve (%VO2R) is considered a more accurate metric for establishing relative exercise intensity than %VO2Max in both low-fit individuals and elite athletes.

Ehrman, Jonathan K. ACSM’s Resource Manual for Guidelines for Exercise Testing and Prescription. 6th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins, 2010. Print.

Parameters:

• vo2Max (float) – given in mL/kg*min
• vo2Rest (float) – given in mL/kg*min

Returns:

VO2, given in mL/kg * min

Return type:

float

running_gross(speed, grade)

For speeds greater than 134 meters/min (5.0 mph). If truly jogging (not walking), this equation can be used for speed of 80-134 meters/min (3-5 mph)

Heyward, Vivian H. “Metabolic Equations for Estimating Gross VO2 (ACSM 2010).” 2010. Advanced Fitness Assessment and Exercise Prescription. 6th ed. Champaign, IL: Human Kinetics, 2010. N. pag. Print.

Parameters:

• speed (float) – given in meters/minute
• grade (float) – given in decimal form

Returns:

VO2Max, given in mL/kg/min

Return type:

float

stepping_gross(height, frequency)

Heyward, Vivian H. “Metabolic Equations for Estimating Gross VO2 (ACSM 2010).” 2010. Advanced Fitness Assessment and Exercise Prescription. 6th ed. Champaign, IL: Human Kinetics, 2010. N. pag. Print.

Parameters:

• height (float) – height of bench, given in meters
• frequency (float) – steps/minute

Returns:

Gross VO2Max, given in mL/kg/min

Return type:

float

treadmill_submax_single_stage(sm1, hr1, hrmax)

Heyward, Vivian H. “Treadmill Submaximal Exercise Tests: single-stage Model.” Advanced Fitness Assessment and Exercise Prescription. 6th ed. Champaign, IL: Human Kinetics, 2010. 85. Print.

Parameters:

• sm1 (float) – distance traversed during the test, given in meters
• hr1 (float) – heart rate in beats/minute
• hrmax (float) – maximal heart rate in beats/minute

Returns:

VO2Max, given in mL/kg/min

Return type:

float

treadmill_submax_vo2_multistage(sm1, hr1, sm2, hr2, hrmax)

Heyward, Vivian H. “Treadmill Submaximal Exercise Tests: Multistage Model.” Advanced Fitness Assessment and Exercise Prescription. 6th ed. Champaign, IL: Human Kinetics, 2010. 85. Print.

Parameters:

• sm1 (float) – distance traversed during the test, given in meters
• hr1 (float) – heart rate in beats/minute
• sm2 (float) – distance traversed during the test, given in meters
• hr2 (float) – heart rate in beats/minute
• hrmax (float) – maximal heart rate in beats/minute

Returns:

VO2Max, given in mL/kg/min

Return type:

float

usop(hrMax, restingHR)

The Uthu2014Su0216rensenu2014Overgaardu2014Pedersen estimation is a VO2Max estimate based on measurements of maximum heart rate and minimum heart rate in well-trained men aged 21 to 51. The formula is most reliable when based on actual measurement of maximum heart rate, rather than an age-related estimates.

The estimation uses the ratio of maximum heart rate (HrMax) to resting heart rate (restingHR) to predict VO2max, and returns VO2Max in mL/kg/minute.

Uth, Niels; Henrik Su0216rensen; Kristian Overgaard; Preben K. Pedersen (January 2004). “Estimation of VO2max from the ratio between HRmax and HRrest–the Heart Rate Ratio Method”. Eur J Appl Physiol. 91 (1): 111u20145. doi:10.1007/s00421-003-0988-y. PMID 14624296.

Parameters:

• hrMax (float) – maximum heart rate, given in beats/minute
• restingHR (float) – given in beats/minute

Returns:

VO2Max, given in mL/kg/min

Return type:

float

walking_gross(speed, grade)

For speeds between 50-100 minter/min (1.9-3.7mph).

Heyward, Vivian H. “Metabolic Equations for Estimating Gross VO2 (ACSM 2010).” 2010. Advanced Fitness Assessment and Exercise Prescription. 6th ed. Champaign, IL: Human Kinetics, 2010. N. pag. Print.

Parameters:

• speed (float) – given in meters/minute
• grade (float) – given in decimal form

Returns:

VO2Max, given in mL/kg/min

Return type:

float

pyexphys.composition module

class pyexphys.composition.BodyFat(gender, age)

Bases: object

Used to estimate body fat percentages

adult_bmi(weight, height)

BMI to body fat percentage formula, Deurenberg, Paul; Weststrate, Jan A.; Seidell, Jaap C. (2007). “Body mass index as a measure of body fatness: Age- and sex-specific prediction formulas”. British Journal of Nutrition. 65 (2): 105u201414. doi:10.1079/BJN19910073. PMID 2043597.

Parameters:

• weight (float) – body weight, given in kilograms
• height (float) – body_height, given in meters

Returns:

body fat percentage

Return type:

float

brozek(body_density)

estimates body fat percentage

Brou017ek, Josef; Grande, Francisco; Anderson, Joseph T.; Keys, Ancel (2006). “Densitometric Analysis of Body Composition: Revision of Some Quantitative Assumptions*”. Annals of the New York Academy of Sciences. 110: 113u201440. doi:10.1111/j.1749-6632.1963.tb17079.x. PMID 14062375.

Parameters:body_density (float) – body density, given in g/cc Returns:body fat percentage Return type:float

child_bmi(weight, height)

BMI to body fat percentage formula, Deurenberg, Paul; Weststrate, Jan A.; Seidell, Jaap C. (2007). “Body mass index as a measure of body fatness: Age- and sex-specific prediction formulas”. British Journal of Nutrition. 65 (2): 105u201414. doi:10.1079/BJN19910073. PMID 2043597.

Parameters:

• weight (float) – body weight, given in kilograms
• height (float) – body_height, given in meters

Returns:

body fat percentage

Return type:

float

ortiz(body_density)

estimates body fat percentage for African American females

Ortiz O, Russell M, Daley TL, Baumgartner RN, Waki M, Lichtman S, et al. Differences in skeletal muscle and bone mineral mass between black and white females and their relevance to estimates of body composition. American Journal of Clinical Nutrition. 1992;55:8u201413.

Parameters:density (body) – body density, given in g/cc Returns:body fat percentage Return type:float

schutte(body_density)

estimates body fat percentage for African American males

Schutte JE, Townsend EJ, Hugg J, Shoup RF, Malina RM, Blomqvist CG. Density of lean body mass is greater in blacks than in whites. Journal of Applied Physiology. 1984;56(6):167u20141649.

Parameters:density (body) – body density, given in g/cc Returns:body fat percentage Return type:float

siri(body_density)

estimates body fat percentage

Siri WE (1961). “Body composition from fluid spaces and density: Analysis of methods”. In Brozek J, Henzchel A. Techniques for Measuring Body Composition. Washington: National Academy of Sciences. pp. 224u2014244.

Parameters:density (body) – body density, given in g/cc Returns:body fat percentage Return type:float

wagner(body_density)

estimates body fat percentage for African American males

Wagner DR, Heyward VH. Validity of two-component models for estimating body fat of black men. Journal of Applied Physiology. 2001;90:649u201456.

Parameters:density (body) – body density, given in g/cc Returns:body fat percentage Return type:float

class pyexphys.composition.Density(gender, age, height, weight)

Bases: object

Estimations of body density, or body fat percentage based on skinfold measurements

body_volume(underwater_weight, residual_volume, gastrointestinal_volume, water_density=1.0)

Parameters:

• underwater_weight (float) – body weight underwater, given in kilograms
• residual_volume (float) – residual volume of the lungs, given in Liters
• gastrointestinal_volume (float) – volume of the gastrointestines, given in Liters
• water_density (float) – density of water

db_at_rv(body_density)

Standard Error of Estimation = 0.0067g/cc (males) Standard Error of Estimation = 0.0061g/cc (females)

Donnelly, Joseph E., Thomas E. Brown, Richard G. Israel, Stephanie Smith-Sintek, Kevin F. O??brien, and Bret Caslavka. “Hydrostatic Weighing without Head Submersion: Description of a Method.” Medicine & Science in Sports & Exercise 20.1 (1988): 66-69. NCBI. Web. 24 Nov. 2016. https://www.ncbi.nlm.nih.gov/pubmed/3343920.

Returns:Body density, given in g/cc Return type:float

skinfold_bhf(sum7skf)

For use with African-American or Hispanic Females

Jackson, A.S., Pollock, M.L., and Ward, A. 1980. Generalized equations for predicting body density of women. Medicine & Science in Sports & Exercise 12: 175-182.

Parameters:sum3skf (float) – sum of skinfold measurements (chest + abdomen + thigh + triceps + subscapular + suprailiac + midaxilla) Returns:Body density, given in g/cc Return type:float

skinfold_cab(sum3skf)

For use with African-American collegiate male and female athletes

Evans, E.M., Rowe, D.A., Misic, M.M., Prior, B.M., and Arngrimsson, S.A. 2005. Skinfold prediction equation for athletes developed using a four-component model. Medicine & Science in Sports & Exercise 37: 2006-2011.

Parameters:sumskf (float) – sum of skinfold measurements (abdomen + thigh + triceps) Returns:body fat percentage Return type:float

skinfold_caw(sum3skf)

For use with white collegiate male and female athletes

Evans, E.M., Rowe, D.A., Misic, M.M., Prior, B.M., and Arngrimsson, S.A. 2005. Skinfold prediction equation for athletes developed using a four-component model. Medicine & Science in Sports & Exercise 37: 2006-2011.

Parameters:sum3skf (float) –

skinfold_child(sum2skf)

For use with black/white boys and girls 6-17 years old

Slaughter, M.H., Lohman, T.G, Boileau, R.A., Horswill, C.A., Stilman, R.J, Van Loan, M.D., and Bemben, D.A. 1988. Skinfold equation for estimation of body fatness in children and youth. Human Biology 60: 709-723.

Parameters:sum2skf (float) – sum of skinfold measurements (triceps + calf) Returns:Body fat percentage Return type:float

skinfold_fa(sum3skf)

For use with white or anorexic females

Jackson, A.S., Pollock, M.L., and Ward, A. 1980. Generalized equations for predicting body density of women. Medicine & Science in Sports & Exercise 12: 175-182.

Parameters:sum3skf (float) – sum of skinfold measurements (triceps + suprailiac + thigh) Returns:Body density, given in g/cc Return type:float

skinfold_wm(sum3skf)

For use with white males 18-61 years old

Jackson, A.S., and Pollock, M.L. 1978. Generalized equations for predicting body density of men. British Journal of Nutrition 40: 497-504.

Parameters:sum3skf (float) – sum of skinfold measurements (chest + abdomen + thigh) Returns:Body density, given in g/cc Return type:float

skinfolf_athlete(sumskf)

For use with female athletes 19-29 years old and male athletes 18-61 years old

Female Athletes Jackson, A.S., Pollock, M.L., and Ward, A. 1980. Generalized equations for predicting body density of women. Medicine & Science in Sports & Exercise 12: 175-182.

Male Athletes Jackson, A.S., and Pollock, M.L. 1978. Generalized equations for predicting body density of men. British Journal of Nutrition 40: 497-504.

Parameters:sumskf (float) – The sum of skinfold measurements, for Males (chest + abdomen + thigh + triceps + subscapular + suprailiac + midaxilla), for Females (triceps + anterior suprailiac + abdomen + thigh) Returns:Body density, given in g/cc Return type:float

class pyexphys.composition.Index(weight, height)

Bases: object

__init__(weight, height)

Parameters:

• weight (float) – body weight, given in kilograms
• height (float) – body height, given in meters

bai(hip_circumference)

The body adiposity index (BAI) is a method of measuring the amount of body fat in humans. The BAI uses the hip circumference (in centimeters) and the height of the participant to estimate body fat. BAI is approximately equal to the percentage of body fat for adult men and women of differing ethnicities.

“A Better Index of Body Adiposity”. Obesity - A Research Journal. Retrieved 7 March 2011.

Parameters:hip_circumference (float) – hip circumference, given in meters Returns:The body adiposity index Return type:float

bmi()

According to the CDC: .. Body Mass Index (BMI) is a person’s weight in kilograms divided by the square of height in meters. A high BMI can be an indicator of high body fatness. BMI can be used to screen for weight categories that may lead to health problems but it is not diagnostic of the body fatness or health of an individual.

Used by the WHO as the standard for recording obesity statistics since the early 1980s, BMI is suitable for recognizing trends within sedentary or overweight individuals because there is a smaller margin of error.

Returns:BMI Return type:float

bmi_prime(upper_limit=25.9)

BMI Prime is the ratio of actual BMI to upper limit optimal BMI, which is the actual BMI expressed as a proportion of upper limit optimal. The ratio of actual body weight to body weight for upper limit optimal BMI is equal to BMI Prime. BMI Prime is a dimensionless number meaning that it does not have units.

Individuals with BMI Prime less than 0.74 are underweight; those with between 0.74 and 1.00 have optimal weight; and those at 1.00 or greater are overweight. BMI Prime is useful clinically because it shows by what ratio a person deviates from the maximum optimal BMI.

Gadzik, James (2006). “‘How much should I weigh?’ Quetelet’s equation, upper weight limits, and BMI prime”. Connecticut Medicine. 70 (2): 81u201488. PMID 16768059

Parameters:upper_limit (float) – The upper limit of optimal BMI Returns:BMI Prime ratio Return type:float

bsi(waist_circumference)

Body Shape Index (BSI) is a metric for assessing the health implications of a given human body based on height, mass and waist circumference. Including waist circumference is believed to make the BSI a better indicator of the health risks from excess weight than the standard Body Mass Index.

Also called the aBSI

“Doctors expose BMI shortcomings”. London Evening Standard. Evening Standard Limited. 2006-01-18. Retrieved 2013-09-12.

Krakauer, Nir Y.; Jesse C. Krakauer (2012-07-18). “A New Body Shape Index Predicts Mortality Hazard Independently of Body Mass Index”. PLOS ONE. 7: e39504. doi:10.1371/journal.pone.0039504. Retrieved 2013-09-12.

Parameters:waist_circumference (float) – waist circumference, given in meters Returns:BSI Return type:float

corpulence()

The Corpulence measure or Ponderal Index is a measure of leanness (corpulence) of a person. Like BMI, the corpulence measure is based on mass and height of an individual. Also called Rohrer’s Index.

The Corpulence index is known to have a number of benefits over Body Mass Index (BMI): - yields valid results even for very short and very tall persons - shown to have a lower false positive rate in athletes - shown to have higher sensitivity, specificity, positive predictive value, and negative predictive value than BMI

Foods and Nutrition Encyclopedia, Audrey H. Ensminger, Marion Eugene Ensminger. p. 1645

Babar, Sultan (March 2015). “Evaluating the Performance of 4 Indices in Determining Adiposity”. Clinical Journal of Sports Medicine. Lippincott Williams & Wilkins). 25 (2): 183

Returns:corpulence Return type:float

sbsi(bsa, vertical_trunk_circumference, waist_circumference)

The Surface-based Body Shape Index (SBSI) outperforms BMI, waist to height ratio (WHtR), waist-to-hip ratio (WHR) and Body Shape Index (BSI) at mortality hazard prediction. SBSI has a generally linear relationship with age and increases with mortality.

“A New Potential Replacement for Body Mass Index | RealClearScience”. www.realclearscience.com. Retrieved 2015-12-31.

Rahman, Syed Ashiqur; Adjeroh, Donald (2015). “PLOS ONE: Surface-Based Body Shape Index and Its Relationship with All-Cause Mortality”. PLoS ONE. 10 (12): e0144639. Bibcode:2015PLoSO..1044639R. doi:10.1371/journal.pone.0144639. PMID 26709925.

Parameters:

• bsa (float) – body surface area, given in meters:superscript:2
• vertical_trunk_circumference (float) – vertical_trunk_circumference, given in centimeters
• waist_circumference (float) – waist_circumference, given in centimeters

Returns:

SBSI

Return type:

float

whr(waist_circumference, hip_circumference)

The waist-to-hip ratio (WHR) has been used as an indicator or measure of health, and the risk of developing serious health conditions. WHR correlates with fertility (with different optimal values for males and females).

According to the World Health Organization(WHO), abdominal obesity is defined as a waistu2014hip ratio above 0.90 for males and above 0.85 for females, or a body mass index (BMI) above 30.0.[5] The National Institute of Diabetes, Digestive and Kidney Diseases (NIDDK) states that women with waistu2014hip ratios of more than 0.8, and men with more than 1.0, are at increased health risk because of their fat distribution.

WHR has been found to be a more efficient predictor of mortality in older people (75+ years of age) than waist circumference or BMI.

“Waist Circumference and Waist-Hip Ratio, Report of a WHO Expert Consultation” PDF. World Health Organization. 8u201411 December 2008. Retrieved March 21, 2012.

Parameters:

• waist_circumference (float) –
• hip_circumference (float) –

Returns:

waist-to-hip ratio

Return type:

float

whtr(waist_circumference)

The waist-to-height ratio (WHtR) is a measure of the distribution of body fat. Higher values of WHtR indicate higher risk of obesity-related cardiovascular diseases; it is correlated with abdominal obesity.

A 2010 study that followed 11,000 subjects for up to eight years concluded that WHtR is a much better measure of the risk of heart attack, stroke or death than the more widely used body mass index.

CM Lee, Huxley RR, Wildman RP, Woodward M (July 2008). “Indices of abdominal obesity are better discriminators of cardiovascular risk factors than BMI: a meta-analysis’”. Journal of Clinical Epidemiology. 61 (7): 646u2014653. doi:10.1016/j.jclinepi.2007.08.012. PMID 18359190.

Schneider; et al. (2010). “The predictive value of different measures of obesity for incident cardiovascular events and mortality.”. The Journal of Clinical Endocrinology & Metabolism. 95 (4): 1777u20141785. doi:10.1210/jc.2009-1584. PMID 20130075.

Parameters:waist_circumference (float) – waist circumference, given in meters Returns:waist-to-height ratio Return type:float

class pyexphys.composition.SurfaceArea(gender, age, weight, height)

Bases: object

Renal clearance is usually divided by the BSA i.e. per 1.73 m:superscript:2 to gain an appreciation of the true glomerular filtration rate (GFR); The cardiac index is a measure of cardiac output divided by the BSA, giving a better approximation of the effective cardiac output; Chemotherapy is often dosed according to the patient’s BSA. Glucocorticoid dosing is also expressed in terms of BSA for calculating maintenance doses or to compare high dose use with maintenance requirement.

__init__(gender, age, weight, height)

Parameters:

• gender (pyexphys.enums.Gender) – The gender of an individual
• age (float) – The age of a person, given in years
• weight (float) – Body weight, given in kilograms
• height (float) – Body height, given in meters

boyd()

Boyd E. The growth of the surface area of the human body. Minneapolis: University of Minnesota Press, 1935. (From: http://www.ispub.com/journals/IJA/Vol2N2/bsa.htm)

costeff()

The Costeff formula is a weight-based formula proposed in 1966, was recently validated for use in pediatrics.

Costeff H, “A simple empirical formula for calculating approximate surface area in children.,” Arch Dis Child, vol. 41, no. 220, pp. 681u2014683, Dec. 1966.

dubois()

DuBois and DuBois’s formula has been shown to be equally as effective in estimating body fat in obese and non-obese patients

DuBois D, DuBois EF. A formula to estimate the approximate surface area if height and weight be known. Arch Med 1916 17:863-71.

fujimoto()

Fujimoto S, Watanabe T, Sakamoto A, Yukawa K, Morimoto K. Studies on the physical surface area of Japanese. 18. Calculation formulae in three stages over all ages. Nippon Eiseigaku Zasshi 1968;5:443u201450.

gehan_george()

Gehan EA, George SL. Estimation of human body surface area from height and weight. Cancer Chemother Rep 1970 54:225-35.

haycock()

Haycock GB, Schwartz GJ, Wisotsky DH. Geometric method for measuring body surface area: A height weight formula validated in infants, children and adults. The Journal of Pediatrics 1978 (93):1:62-66.

mosteller()

Along with Boyd, considered to be more accurate formula for body surface area than other formulas. Maintained the most clinically acceptable and fairly constant degree of bias as children’s age increases.

Mosteller RD. Simplified Calculation of Body Surface Area. N Engl J Med. 1987 Oct 22;317(17):1098. (letter)

schlich()

Schlich, E; Schumm, M; Schlich, M (2010). “3-D-Body-Scan als anthropometrisches Verfahren zur Bestimmung der spezifischen Körperoberfläche”. Ernährungs Umschau. 57: 178u2014183.

shuter_aslani()

Shuter, B; Aslani, A (2000). “Body surface area: Du bois and Du bois revisited”. European Journal of Applied Physiology. 82 (3): 250u2014254. doi:10.1007/s004210050679.

takahira()

Fujimoto S, Watanabe T, Sakamoto A, Yukawa K, Morimoto K. Studies on the physical surface area of Japanese. 18. Calculation formulae in three stages over all ages. Nippon Eiseigaku Zasshi 1968;5:443u201450.

pyexphys.composition.daily_water_need(weight)

The amount of water needed daily by the body based on body weight

Parameters:weight (float) – body weight, given in kilograms Returns:estimated daily water need (in Liters) Return type:float

pyexphys.mets module

class pyexphys.mets.MET(value, code, description)

Bases: object

The Metabolic Equivalent of Task (MET), or metabolic equivalent, is a measure expressing the energy cost of physical activities. METs are defined as the ratio of metabolic rate (and therefore the rate of energy consumption) during a specific physical activity to a reference metabolic rate.

One MET is defined as 1 kcal/kg/hour and is roughly equivalent to the energy cost of sitting quietly. A MET also is defined as oxygen uptake in ml/kg/min with one MET equal to the oxygen cost of sitting quietly, equivalent to 3.5 ml/kg/min.

1 MET = 1kcal/kg*h = 4.184 kJ/kg*h = 1.162 W/kg

__init__(value, code, description)

Parameters:

• value (float) –
• code (str) – The unique identifier for the activity
• description (str) – Description of the activity

to_kcal(weight)

Estimates energy expenditure in kilocalories/minute

Ehrman, Jonathan K. ACSM’s Resource Manual for Guidelines for Exercise Testing and Prescription. 6th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins, 2010. Print.

Parameters:weight (float) – body weight, given in kilograms Returns:kilocalories/minute Return type:float

pyexphys.mets.stairmaster_mets(setting)

For use in submaximal tests on the StairMaster 4000 PT step ergometer.

Howley, Edward T., Dennis L. Colacino, and Thomas C. Swensen. “Factors Affecting the Oxygen Cost of Stepping on an Electronic Stepping Ergometer.” Medicine & Science in Sports & Exercise 24.9 (1992): n. pag. NCBI. Web. 10 Nov. 2016.

Parameters:setting (int) – the setting of the step ergometer Returns:VO2:subscript:2max in kcal/kg*hour Return type:float

pyexphys.mets.target(vo2max, intensity)

Used to estimate a MET value for a given VO2max intensity

Ehrman, Jonathan K. ACSM’s Resource Manual for Guidelines for Exercise Testing and Prescription. 6th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins, 2010. Print.

Parameters:

• vo2max (float) – A VO2Max value
• intensity (float) – The intensity of the activity

Returns:

MET value

Return type:

float

pyexphys.mets.to_kcal(mets, weight)

Estimates energy expenditure in kilocalories/minute

Ehrman, Jonathan K. ACSM’s Resource Manual for Guidelines for Exercise Testing and Prescription. 6th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins, 2010. Print.

Parameters:

• mets (float) – MET value
• weight (float) – body weight, given in kilograms

Returns:

kilocalories/minute

Return type:

float

pyexphys.strength module

The strength module contains equations for estimating strength in weightlifting exercises, estimating 1-repetition maximum values, and metrics for comparing weightlifting performances across weight classes, and genders.

class pyexphys.strength.Abadie(reps)

Bases: pyexphys.strength.RMEstimator

Studied population was 30 college aged females. Performs best when repetitions range from 5 to 10

predict(weight)

Parameters:weight (float) – weight lifted, given in kilograms Returns:1-RM, given in kilograms Return type:float

weight(rm)

Estimates the weight lifted for the number of reps based on the 1-RM argument

Parameters:rm (float) – 1-RM, given in kilograms Returns:weight lifted, given in kilograms Return type:float

class pyexphys.strength.Baechle(reps)

Bases: pyexphys.strength.RMEstimator

BAECHLE, T.R. and EARLE, R.W. and WATHEN, D. (2000) Resistance training. In: BAECHLE, T.R. and EARLE, R.W., eds. Essentials of Strength Training and Conditioning. 2nd ed. Champaign, IL: Human Kinetics, p. 395-425

predict(weight)

Parameters:weight (float) – weight lifted, given in kilograms Returns:1-RM, given in kilograms Return type:float

weight(rm)

Estimates the weight lifted for the number of reps based on the 1-RM argument

Parameters:rm (float) – 1-RM, given in kilograms Returns:weight lifted, given in kilograms Return type:float

class pyexphys.strength.Brzycki(reps)

Bases: pyexphys.strength.RMEstimator

The Brzycki formula for estimating a 1-Repetition Maximum (1-RM). For repetitions less than 10, the Brzycki formula returns slightly higher estimated 1-RM than the Epley formula. The two formulas are identical at 10 repetitions.

predict(weight)

Parameters:weight (float) – weight lifted, given in kilograms Returns:1-RM, given in kilograms Return type:float

twoSet(weight, rep2, weight2)

The Brzycki Two Set Max formula is a 1-RM prediction equation based on the number of repetitions to fatigue obtained two submaximal sets.

Brzycki, M. 2000. Assessing strength. Fitness Management 16(7): 34-37

Parameters:

• weight (float) – weight lifted, given in kilograms
• rep2 (int) – Repetitions in second submaximal set
• weight2 (float) – weight lifted in second submaximal set, given in kilograms

Returns:

1-RM, given in kilograms

Return type:

float

weight(rm)

Estimates the weight lifted for the number of reps based on the 1-RM argument

Parameters:rm (float) – 1-RM, given in kilograms Returns:weight lifted, given in kilograms Return type:float

class pyexphys.strength.Epley(reps)

Bases: pyexphys.strength.RMEstimator

The Epley formula for estimating a 1-Repetition Maximum (1-RM). For repetitions less than 10, the Epley formula returns slightly lower estimated 1-RM than the Brzycki formula. The two formulas are identical at 10 repetitions.

EPLEY, B. (1985) Poundage Chart. Boyd Epley Workout. Lincoln, NE: Body Enterprises.

predict(weight)

Parameters:weight (float) – weight lifted, given in kilograms Returns:1-RM, given in kilograms Return type:float

class pyexphys.strength.Landers(reps)

Bases: pyexphys.strength.RMEstimator

LANDERS, J. (1985) Maximums Based on Reps. National Strength and Conditioning Association Journal. 6: 60-61.

percent()

Returns:percentage of 1-RM Return type:float

predict(weight)

Parameters:weight (float) – weight lifted, given in kilograms Returns:1-RM, given in kilograms Return type:float

weight(rm)

Estimates the weight lifted for the number of reps based on the 1-RM argument

Parameters:rm (float) – 1-RM, given in kilograms Returns:weight lifted, given in kilograms Return type:float

class pyexphys.strength.Lombardi(reps)

Bases: pyexphys.strength.RMEstimator

For use with less than 11 repetitions

LeSuer, Dale A.; McCormick, James H.; Mayhew, Jerry L.; Wasserstein, Ronald L.; Arnold, Michael D. (November 1997). “The Accuracy of Prediction Equations for Estimating 1-RM Performance in the Bench Press, Squat, and Deadlift”. Journal of Strength and Conditioning Research. 11 (4): 211u2014213. doi:10.1519/00124278-199711000-00001

predict(weight)

Parameters:weight (float) – weight lifted, given in kilograms Returns:1-RM, given in kilograms Return type:float

weight(rm)

Estimates the weight lifted for the number of reps based on the 1-RM argument

Parameters:rm (float) – 1-RM, given in kilograms Returns:weight lifted, given in kilograms Return type:float

class pyexphys.strength.Mayhew(reps)

Bases: pyexphys.strength.RMEstimator

For use with less than 15 repetitions. Studied population was 434 (185 college men, 251 college women)

LeSuer, Dale A.; McCormick, James H.; Mayhew, Jerry L.; Wasserstein, Ronald L.; Arnold, Michael D. (November 1997). “The Accuracy of Prediction Equations for Estimating 1-RM Performance in the Bench Press, Squat, and Deadlift”. Journal of Strength and Conditioning Research. 11 (4): 211u2014213. doi:10.1519/00124278-199711000-00001

football()

Estimating the maximal 1-RM using results from the NFL-225 Bench Press Test

Mayhew, J.L., Ball, T.E., Arnold, M.D., and Bowen, J.C. 1992. Relative muscular endurance performance as a predictor of bench press strength in college men and women. Journal of Applied Sport Science Research 6: 200-206

Mayhew, Jerry L., John S. Ware, Michael G. Bemben, Bill Wilt, Tom E. Ward, Bill Farris, Joe Juraszek, and John P. Slovak. “The NFL-225 Test as a Measure of Bench Press Strength in College Football Players.” Journal of Strength and Conditioning Research 13.2 (1999): 130-34. Web.

Returns:1-RM, given in kilograms Return type:float

percent()

Returns:percentage of 1-RM Return type:float

predict(weight)

Parameters:weight (float) – weight lifted, given in kilograms Returns:1-RM, given in kilograms Return type:float

weight(rm)

Estimates the weight lifted for the number of reps based on the 1-RM argument

http://www.unm.edu/~rrobergs/478RMStrengthPrediction.pdf

Parameters:rm (float) – 1-RM, given in kilograms Returns:weight lifted, given in kilograms Return type:float

class pyexphys.strength.McGlothin(reps)

Bases: pyexphys.strength.RMEstimator

predict(weight)

Parameters:weight (float) – weight lifted, given in kilograms Returns:1-RM, given in kilograms Return type:float

weight(rm)

Estimates the weight lifted for the number of reps based on the 1-RM argument

LeSuer, Dale A.; McCormick, James H.; Mayhew, Jerry L.; Wasserstein, Ronald L.; Arnold, Michael D. (November 1997). “The Accuracy of Prediction Equations for Estimating 1-RM Performance in the Bench Press, Squat, and Deadlift”. Journal of Strength and Conditioning Research. 11 (4): 211u2014213. doi:10.1519/00124278-199711000-00001

Parameters:rm (float) – 1-RM, given in kilograms Returns:weight lifted, given in kilograms Return type:float

class pyexphys.strength.RMEstimator(reps)

For predicting 1 repetition maximum(1-RM), a number of estimator classes are provided that each use a different equation for predicting 1-RM. Each of these classes are subclasses of RMEstimator and implement the same interface. Developers can change the equation for predicting 1-RM by changing the estimator class in their application rather than changing their application logic. Each class can be constructed by providing the reps parameter and can use the predict method, with a weight argument to return the 1-RM value (in kg).

__init__(reps)

Parameters:reps (int) – repetitions performed

class pyexphys.strength.ReynoldsCP(reps)

Bases: pyexphys.strength.RMEstimator

The Reynolds formula for the Chest Press exercise. Weight parameter is the 5 rep maximum (5-RM) in kg.

predict(weight)

Parameters:weight (float) – weight lifted, given in kilograms Returns:1-RM, given in kilograms Return type:float

class pyexphys.strength.ReynoldsLP(reps)

Bases: pyexphys.strength.RMEstimator

The Reynolds formula for the Leg Press exercise. Weight parameter is the 5 rep maximum (5-RM) in kg.

predict(weight)

http://www.unm.edu/~rrobergs/478RMStrengthPrediction.pdf

Parameters:weight (float) – weight lifted, given in kilograms Returns:1-RM, given in kilograms Return type:float

class pyexphys.strength.Wathan(reps)

Bases: pyexphys.strength.RMEstimator

The Wathan equation for predicted the 1 repetition maximum (1-RM). The Wathan equation most closely estimates 1-RM for all upper body exercises, the leg press, and dorsiflexion exercises, and can be used to determine resistance training intensities for older adults.

LeSuer, Dale A.; McCormick, James H.; Mayhew, Jerry L.; Wasserstein, Ronald L.; Arnold, Michael D. (November 1997). “The Accuracy of Prediction Equations for Estimating 1-RM Performance in the Bench Press, Squat, and Deadlift”. Journal of Strength and Conditioning Research. 11 (4): 211u2014213. doi:10.1519/00124278-199711000-00001

predict(weight)

Parameters:weight (float) – weight lifted, given in kilograms Returns:1-RM, given in kilograms Return type:float

weight(rm)

Estimates the weight lifted for the number of reps based on the 1-RM argument

Parameters:rm (float) – 1-RM, given in kilograms Returns:weight lifted, given in kilograms Return type:float

pyexphys.strength.relative(weight, rm)

Parameters:

• weight (float) – weight lifted, given in kilograms
• rm (float) – 1-RM, given in kilograms