The Arm Crank Protocol developed at the University of Toronto can be used to assess the physical fitness of wheelchair-dependent individuals. Forearm cranking is performed at 3 different submaximal power outputs, so that the steady state heart rate is 40%, 60% and 80% of maximal heart rate for age.
Discontinuous Arm Crank Testing
age adjusted maximal heart rate in beats per minute =
= 220 - (age in years)
Perform three 5-7 minute steady state workouts at power outputs of 40%, 60% and 80% of the predicted age-adjusted maximal heart rate.
Power Output to Oxygen Uptake Conversion
Calculate the oxygen uptake for each workout from the power output.
For disabled males,
estimated oxygen uptake in mL/min =
= ((power output in watts) * 18.2) + 395.2
For disabled females,
estimated oxygen uptake in mL/min =
= ((power output in watts) * 17.6) + 352.8
Astrand-Rhyming Age Correction Factor
A single age-dependent correction factor is used for both men and women.
|
age in years
|
factor
|
|
25
|
1.00
|
|
35
|
0.87
|
|
45
|
0.78
|
|
55
|
0.71
|
|
65
|
0.65
|
This can be approximated by the formula
Astrand-Rhyming age correction factor =
= (0.0001143 * ((age in years) ^2)) - (0.018886 * (age in years)) + 1.3975714
Maximum Oxygen Uptake Estimate for Each Workload
For males:
maximum oxygen uptake in mL/min =
= (oxygen uptake in mL/min) * (195-61) / ((heart rate in beats per minute) - 61) * (age correction factor)
For females:
maximum oxygen uptake in mL/min =
= (oxygen uptake in mL/min) * (198-72) / ((heart rate in beats per minute) - 72) * (age correction factor)
Determine Maximum Oxygen Uptake
Disregard the lowest estimated maximum oxygen uptake of the 3 values.
predicted maximum oxygen uptake =
= AVERAGE (highest and middle maximum oxygen uptake estimate)
predicted maximum oxygen uptake per kilogram body weight =
= (predicted maximum oxygen uptake in mL/min) / (body weight in kilograms)
Interpretation
|
|
predicted maximum oxygen uptake in mL / min / kg
|
|
Fitness Level for Persons with Paraplegia
|
Female
|
General Male Population
|
Elite Male Athletes
|
|
poor
|
< 5.4
|
< 10.5
|
< 17.2
|
|
below average
|
5.4 - 16.2
|
10.5 - 21.9
|
17.2 - 31.5
|
|
average
|
16.3 - 27.1
|
22.0 - 33.4
|
31.6 - 45.9
|
|
above average
|
27.2 - 38.0
|
33.5 - 44.9
|
46.0 - 60.3
|
|
excellent
|
> 38.0
|
> 44.9
|
> 60.3
|
