We often hear alot about this in the news but what does it really mean? Well I thought I would share some interesting info from this anatomy text book I am reading right now before I renew one of my personal training certifications. The first part is about testosterone;
"one must keep in mind that high-intensity endurance exercise can have a very dramatic catabolic (breaking down) tissue response and increases in testosterone may be related to the need for maintaining protein synthesis to keep up with protein loss. Hypertrophy (muscle growth) does not take place with endurance training. In fact, oxidative stress may actually promote a decrease in muscle fiber size in order to optimize oxygen transport kinietics into the cell."
In other words, lots of aerobic activity will actually breakdown muscle mass. Your body will do this as a defense mechanism to become more efficient at aerobic activity. It also says that your muscles do not get larger because of aerobic activity. So long story short, the next time you think all you need to do is spin for your leg development, think again!!!
Next passage is on growth hormone and its release.
"the secretion of growth hormone and thus the amount in the blood varies according to time of day, with the highest levels observed at night during sleep. Various external factors, such as age, gender, sleep, nutrition, alcohol consumption, and exercise, all alter growth hormone release patterns."
Now growth hormone is mostly important because it helps us recover from exercise and feeds on body fat. So the more you exercise, sleep, and the less you drink, the higher your growth hormone levels are and the more fat you will burn. Another, reason why you shouldnt drink and go to bed early!!!
There you go