Assignment task:
Mary starts jogging and continues as a modest pace for 2 hours. Her muscles use ATP to power the contractions that cause jogging. In each muscle she has enough ATP to last about 4 -6 seconds or all out effort, but because she is jogging that amount of ATP may last as long as 10-30 seconds. Paradoxically, when Jill, a research scientist measures the levels of ATP in Mary's active muscles she gets the same value every time she measures it. She takes the first measurement before exercise starts, and thereafter measures it every 10 minutes during and after exercise. The value she gets is approximately 8mM, and it does not seem to change much at all over the entire exercise period. Nor is it different before or after exercise. These findings by Jill are not unusual...other scientist have reported similar values in similar circumstances. Can you explain this? Why does she not run out of ATP? Where does the energy come from for jogging? Is she really using ATP?