Question

Turtle (220 lb individual) performs the Margaria-Kalamen leg power test (stair test). His time between the 3rd and 9th steps is 0.75 seconds (each step is 6 inches in height). What is his power output in kgm/sec? Round your answer to the nearest whole number.

• A. 157 kgm/sec.

• B. 135 kgm/sec.

• C. 122 kgm/sec.

• D. 110 kgm/sec.

Answer 1

The power, P, exerted by the turtle is calculated by,

where,

m is the mass of the athlete; given 220 lb = 99.79 kg

h is the vertical height between the third and ninth steps; given each step height 6 inches and vertical height between 3rd and 9th steps is 6×6= 36 inches = 0.914 m

t is the time between stepping on the third and ninth steps; given time is 0.75 sec

g is acceleration due to gravity, approximately 9.81 m/s²

P = 9.81×99.79×0.914/0.75 = 1193.00 watts.

Convert watts to kgm/s

1 watt = 0.10197 kg-m/s

Then 1193.00 watts = 121.66 kgm/s

Hence the answer is 122kgm/s