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I advocate that bodybuilders at all levels initiate an aerobics program, because it has many benefits. First, it enhances general cardiovascular fitness, and being healthy in heart and lung efficiency is a boon for a competing bodybuilder. Second, this better level of general fitness increases metabolism. This makes your system much more efficient (than would be the case if you were sedentary) at assimilating the heavy protein intake necessary for bodybuilders. Third (and the reason I did cardio year-round when I was competing), it increases endurance so that when I launched into my contest-prep period where I started to train faster, I was ready for the pace from a fitness standpoint. The fourth main benefit is that doing cardio all year means you are able to take in a few more calories on a daily basis than would be the case if all you did was lift.
My favorite form of cardio is power walking. I have tried stationary bikes and treadmills, but the concept of cycling or walking furiously and going nowhere bored the crap out of me. So power walking became my thing during the offseason, and I resorted to a bike or treadmill only during the offseason when the weather (I live in England, remember) sabotaged outside activities.
In the offseason, I completed 30-minute power-walking sessions four times a week, first thing in the morning soon after I awoke and before breakfast. I just drank some water and then off I’d go. After having not eaten for 10 hours or so, I was in a low-carb state and, therefore, my body would more readily turn to fat for fuel. The pace was brisk, so I was breathing hard quickly. I took long strides and swung my arms to encourage general cardio stimulation. Writer Peter McGough once watched me power walking back to my house, and he said that with my brisk pace, long strides and swinging arms, plus the fact that I weighed 275, I looked like Frankenstein on speed. Moments like that make it all worthwhile!
Switching to the contest-prep period, I increased my aerobic activity to a high of two 30-minute sessions a day, six days a week. I completed a power-walking session first thing in the morning and then did a stationary-bike session in the evening.
During the contest-prep period, when my aerobic workload was much higher and my body more depleted, it was often tough to contemplate two 30-minute sessions a day, six days a week. But I drove myself on with a do-or-die attitude that meant the work had to be completed. I had to instill in myself the belief that I was training harder, dieting smarter and was more disciplined in meeting my aerobic quota than anyone else.
For general health maintenance and to gain the bodybuilding advantages of being cardiovascularly fit, I recommend doing at least three, and preferably four, 30-minute cardio sessions a week. Try to complete them early in the morning, be consistent and, by walking away from the gym, you will become a better bodybuilder.