What hormones are affected before, during, and after a workout?

[juiceman]

I hear different stories in different magazines and such about what hormones are affected when lifting. During exercise is IGF-1 or test or GH affected? I know they are slightly affected when doing deadlifts or squats, but for other exercises i mean. Anyone have a clue? Do test levels drop after working out?
Thanks for your time and your help.
Mike

[Travis Stenersn]

I'll write you a synopsis later today.
For now if you are truly curious, check out the Strength and Conditioning Journal vol. 23 issue 3
Should be available online at www.nsca-lift.org

It might be one of the 'members only' ones.. if thats the case just hold out till later today when I'm done my chem lab! =)

[Travis Stenersn]

Hormones that respond to exercise:

Testosterone: Heavy resistance training(85-95% 1RM) and moderate to high volumes have been shown to cause acute increases in testosterone. This increases aren't huge, and don't last very long. It was previously though that these increases were merely acute, and resistance training and no effect on chronic serum T levels. Studies recently have shown the opposite, that T levels in perviously untrained males were increased following 8 weeks of resistance training. Research has also examined the effect free T to SHBG bound T has on strength and hypertrophyy. They found a correlation of a higher free to bound T ratio with muscle hypertrophy, greater strength and better performance.

GH and IGF1:
Exercise containing moderate to high volumes, high intensity and shorter rest periods have been shown to greatly increase acute serum GH levels. It's probably due to the increase of lactic acid concentration in the blood. Relationships have been found with increased serum GH levels and increased Type I and II muscle fiber hypertrophy. GH also signals the production of insulin like growth factors, like IGF1. Both GH and IGF1 are known to increase muscle hypertrophy.

Insulin:
It's well known that exercise has a positive effect on muscle insulin sensitivity. Protein/carb supplementation post exercise can greatly increase the levels of insulin in the body. Insulin acts like a key to open gates to the cells for nutrients like glucose and amino acids to enter into the cell for (hopefully!) anabolic processes within the cells or for energy(catabolic processes). Interestingly, an inverse relationship between serum testosterone and insulin can be observed.

Cortisol:
Cortisol is responsible for allowing the breakdown of amino acids into glucose to maintain blood glucose levels. Studies have shown chronic decreases in resting cortisol levels following a heavy resistance training program. However, overtraining can lead to the opposite!

Catecholamines (Epinephrine and NorE)

Resistance training has been shown to cause acute increases in these metabolic hormones. The effects of catecholamines on muscle hypertrophy are unknown.

Keep in mind that this is all a bit different for females!!