25-12-03
Effects of exercise on cardiac output
(For results see graph paper)
Analysis
After the initial period of rest in both girls and boys heart rates rose slightly with light exercise (walking), and then fell again slightly back towards the original resting point. Then during the period of anticipation of exercise the males heart rate rose by a further 1 beat per 6 seconds, whereas the females took a dramatic leap, and rose by 3.5 beats per 6 seconds, or 35 beats per minute. Then for the exercise period the males rose by nearly 4 beats per 6 seconds, or 40 beats per minute. Whereas the females heart rate only rose by 3 beats per 6 seconds, or 30 beats per minute.
Throughout the experiment, female's heart rate as been higher than that of the males. 1 minute of the exercise the female's heart rate had dropped from 15 betas per 6 seconds to 13 beats per 6 seconds. The males had dropped from 13 to 11.5. After 2 minutes the females Heart rate continued this trend of dramatic decrease whereas the males only dropped by 0.5 of a beat per 6 seconds. This is when the females heart rate is at its closest to the males, quite suddenly as the graph shows the female heart rate stops decreasing at such a heavy rate as before and only decreases 0.12 of a heart beat per 6 seconds or 1.2 beats per minute. The males heart rate decreases by a further 1 beat per 6 seconds, to 10 beats per 6 seconds. At 4 and 5 minutes both genders heart rate start to level off to their resting heart rate, though not actually getting there.
Walking only instils a short increase because the heart only needs to pump a bit extra blood round the body for the bodies muscles will not be working particularly hard, therefore they will only require a small amount of extra oxygen. Therefore the heart will only contract slightly faster than it was when it was resting.
Then during the 2nd resting period the heart starts to return to its normal pace, because not as much oxygen is needed