In each of these exercises, you will be calculating the potential energy created during one repetition of the exercise. To do so, you need to do two things:

1. Measure the height change of the exerciser from the bottom position of the exercise to the top position of the exercise.

For example, if the exerciser is doing pushups, have the person get into the lower position, measure the height of their shoulder from the floor, then have them push up to the upper position and see where their shoulder is now. The difference between these two heights will be the height change during one repetition of the exercise.

2. Find the mass for the calculation. This involves two parts: a. Finding the mass of the person doing the exercise. If you know your body weight in pounds, divide this number by 2.2 to find your mass in kilograms. b. Estimate how much of your body mass you are raising with the exercise you are doing. For example, in a calf raise, you raise your entire body (except for your toes), so you can estimate using your entire body mass. However, a pushup can be estimated to use about half of your body mass. Use your best judgment for each exercise.

Percentages of Total Body Weight
Segment	Males	Females	Average
Head	8.26	8.2	8.23
Whole Trunk	55.1	53.2	54.15
Thorax	20.1	17.02	18.56
Abdomen	13.06	12.24	12.65
Pelvis	13.66	15.96	14.81
Total Arm	5.7	4.97	5.335
Upper Arm	3.25	2.9	3.075
Forearm	1.87	1.57	1.72
Hand	0.65	0.5	0.575
Forearm & Hand	2.52	2.07	2.295
Total Leg	16.68	18.43	17.555
Thigh	10.5	11.75	11.125
Leg	4.75	5.35	5.05
Foot	1.43	1.33	1.38
Leg & Foot	6.18	6.68	6.43

Table Data: Plagenhoef et al., 1983

Take data for each exercise and enter it into the table below. Different exercises can be done by different people or the same person can do each one. Perform each exercise for 20 seconds and see how many you can do. Or, take it easy if you prefer.

Clean Up:

• Lay meter stick and tape measure in the center of the row.

• Make sure bathroom scale has been returned to the instructor's bench in the front of the lab.

The Physics Olympics - Data Sheet

Name: _____________________________________________ Date: _____________________

Exercise	Height change (m)	Estimated mass (kg)	PE for single repetition (J) PE = mgh	Number of repetitions in 20 seconds	Total energy created	Power output (Watts)

Filling in the table:

• To calculate the potential energy (PE) in a single repetition, multiply the estimated mass by the height change and by g (9.8m/s²).

• To calculate the total energy created, multiply the potential energy from a single repetition by the number of repetitions done in 20 seconds.

• To find the power output, divide the total potential energy created during all the repetitions by the total time (20 seconds).