Short Intense Workouts Are Better

Short & Stimulating Workouts
Do you perform long workouts? Pat yourself on the back for being able to stay in the gym for quite awhile? Training for long sessions is fine for cardio/aerobic training aimed at either endurance and/or fat burning, but not the wisest course for muscle building. That's because in the weight training realm you can actually train too long. That's right - by training for extended lengths of time you may be doing more harm than good.
What's wrong with going long in your training? Testosterone and energy output. Vince Gironda noted that there is a significant drop off of working testosterone at about the 45 minute mark in a workout. When your testosterone levels dive, its time to hang it up for the ay. Otherwise, to keep pushing at that point won't bring nearly as much muscle gains - in fact things might start going catabolic instead of anabolic.
Energy levels drop off as well when you extend your workout a long time. The exercises that are performed in the latter end of a long work out get the leftovers - the scraps of the workout. When energy and testosterone flow are both low, motivation also runs dry as well, and that mix makes for tough going.
It is far wiser to get in gym and put in a hard hitting workout, then get out. Aim at training for no longer than 45 minutes per session. Set up your training schedule so that you can get it wrapped up without going into the zone where testosterone diminishes. This may take a little time scheduling, and may require some split sessions, but if you are serious about building muscle, you want to get the very most out of each training session. That means short and super stimulating.
If you train hard and quick, you can get in a lot of weight lifting in 45 minutes. It helps as well to stay totally focused on the workout and the muscles you are training and avoid chatting too much. Stuffing your workout into a 45 minute time frame will help you prioritize your workout and put the main and most important things first and foremost.
There are always exceptions to the rule and an occasional longer session, particularly if you use it as a shock session, can work on a rare basis. However, for you main training approach, try to get out of the gym in 45 minutes or less consistently. Hit your muscles hard and then let them get their earned rest.

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