INTERPLAY OF THE ENERGY SYSTEMS

Quantifying intensity

• Calculation of Maximum Heart Rate• The easiest and best known method to

calculate your maximum heart rate (MHR) is to use the formula

• MHR = 220 - Age

http://www.brianmac.co.uk/maxhr.htm

Quantifying intensity• % MHR and %VO2 Max• It is possible to estimate your exercise intensity as a

percentage of VO2 max from your training heart rate. David Swain (1994) and his US based research team using statistical procedures examined the relationship between %MHR and %VO2 Max. Their results led to the following regression equation:

• %MHR = 0.64 × %VO2 Max + 37 • The relationship has been shown to hold true across

sex, age and activity.

http://www.brianmac.co.uk/maxhr.htm

Quantifying intensity

• A calculator to convert %MHR to %VO2 max and vice versa can be found at: http://www.brianmac.co.uk/maxhr.htm

• If using Excel:

Quantifying intensityA study by David Swain and his US-based research team has

criticised the mathematical methods used to derive the regression equations in previous research. Using more correct statistical procedures, they re-examined the relationship between % VO2 max and % HR max and found that the ACSM formula underestimates HR at the target values of % VO2 max. Their results led to a regression equation of % HR max = 0.64 x % VO2 max + 37. This means that 40% VO2 max corresponds to 63% HR max, 60% VO2 max corresponds to 75% HR max, 80% VO2 max corresponds to 88% HR max, and 85% VO2 max corresponds to 92% HR max.

http://www.pponline.co.uk/encyc/0186.htm

%MHR ↔ %VO2 max

convert %MHR → %VO2 max

convert %VO2 max → %MHR

%MHR %VO2 max %VO2 max %MHR

100%MHR = 98%VO2 max 100%VO2 max = 101%MHR

92%MHR = 86%VO2 max 90%VO2 max = 95%MHR

85%MHR = 75%VO2 max 80%VO2 max = 88%MHR

70%MHR = 52%VO2 max 70%VO2 max = 82%MHR

60%MHR = 36%VO2 max 60%VO2 max = 75%MHR

INSTRUCTIONS:

1. Using the Energy Systems Graph complete the Excel Spreadsheet for the:

i. 400m 5 second interval “at point in time”ii. 800m 10 second interval “at point in time” and 10

second cumulative splitsiii. 1500m 30 second interval “at point in time” and 30

second cumulative splits

Note: Cumulative refers to the amount of energy produced by each system over a 10 second (800m) or 30 second (1500m) period of time.

INSTRUCTIONS:

2. Use the Excel Energy Systems Interplay tables and GPS “speed – time splits” bar graphs to create “at this point in time” Energy Systems Interplay / Contribution bar graphs for each of the 400m, 800m and 1500m races.

3. Use the Excel Energy Systems Interplay tables and GPS “speed & HR vs time” line graphs to create “cumulative” Energy Systems Interplay / Contribution line graphs for each of the 400m, 800m and 1500m races.

400m track

400m track

0 5 10 15 20 25 30 35 40 45 50 55 60

Speed (km/h) HR (bpm)

400m track

Speed (km/h) HR (%MHR)

0 5 10 15 20 25 30 35 40 45 50 55 60

0 5 10 15 20 25 30 35 40 45 50 55 60

800m track

800m track

Speed (km/h) HR (bpm)

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140

800m track

Speed (km/h) HR (%MHR)

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140

1500m track

1500m track

Speed (km/h) HR (bpm)

0 30 60 90 120 150 180 210 240 270 300 330

1500m track

Speed (km/h) HR (bpm)

0 30 60 90 120 150 180 210 240 270 300 330

0 30 60 90 120 150 180 210 240 270 300 330