This article is from the Hardgainer Bodybuilding & Weightlifting FAQ, by Frank J. Kelly and Craig R. Sadler with numerous contributions by others.
Today, most professional athletes cycle their intensity. Over the
past few years, techniques have been found to better the athlete's
performance, however they take a much higher toll on the body. The
athlete must also reach PEAK fitness and strength at the right time.
For both of these reasons, athletes will cycle the intensity of
their exercise routine.
.2 Why MUST hardgainers cycle intensity?
Hardgainers don't have the genetic gifts that
easy gainers do. Even if they did they should include cycling for
spurring extra gains when plateaus/stagnation set in. Remember, once
you have overtrained, you can't bully your way out of it. The only
solution is to drop your intensity temporarily. Cycling is a planned
and organized effort to arrange irregular progress into a regular
progression of 'ups' and 'downs', with each new 'up' or 'down'
being a little higher than the previous one. After a cycle (of
12-20 weeks) one should look at having gained 15-20 pounds on the
bench press, 20-30 pounds on the squat and Deadlift. Maintaining
this progress for 12-18 months will give you tremendous gains.
 
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