If you really want to pack on the muscle mass in the shortest time possible you would be wise for you to limit your workout to no longer than 30-60 minutes in length. Basically the longer your workout the greater your chances are of over-training; drug free trainees in particular must be especially cautious of lengthy exercise sessions.

Numerous studies have shown that natural Testosterone and Growth hormone (GH) levels begin level off and decline after 30-45 minutes of intensive exercise (the more intensive the exercise the quicker the drop in Testosterone and GH levels). Testosterone and GH are primary hormones utilized in increasing muscular protein synthesis (i.e. the building of the new lean muscle mass). An exercise induced decline in Testosterone and GH accompanies a rise in the catabolic hormone Cortisol; elevated Cortisol levels has a negative impact on increases and retention of muscle mass and strength, literally eating away at muscle tissue.

If you continue to exercise intensely after 30-60 minutes of output you risk losing existing muscle mass as well as retarding any potential gains that you could have made from your workout. Generally the harder you train the briefer your workouts must be.

Another important benefit of doing shorter workouts is that you are forced to focus during the entire training session. With 30-60 minutes you know that you have a limited amount of time and must put total focus into each and every set in order to derive a positive benefit from your workout. As a result of this focus each and every work set is more likely to be completed with the required intensity to trigger the body’s natural growth mechanism.

Longer duration workouts by comparison can cause a trainee to loss focus and intensity; in order to get through the entire workout the trainee will be forced to pace him or herself, thus reducing intensity. A trainee will have no other choice as he/she has to conserve enough energy to make it through the marathon training method. Since intensive exercise is a requirement for building impressive drug free lean muscle mass, you would do well the keep your workouts on the briefer side of the fence.

Of course some trainees may argue that they can train intensely at the beginning of a long session and reduce the intensity as the workout progresses, the draw back here is that beyond a certain point performing additional sets is like beating a dead horse, not only are they unnecessary but can deplete valuable recovery resources (energy) which could be better utilized for actual muscle growth.

So keeping your workouts on the shorter side will keep your Testosterone and Growth hormone output at optimal muscle building levels, Keep the muscle burning hormone Cortisol in check, Allow you to train at a high enough levels of intensity to trigger rapid muscle growth, Allow you to actually benefit from your training by not depleting your recovery resources.

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