Dr. Karlie Moore - Fit For Duty Consulting

A few weeks ago I gave you the good news that we don’t lose muscle mass very easily; before the age of 50 you can take a break from resistance training and not experience huge losses in strength (read more about that here). Unfortunately, taking an extended break from aerobic training WILL result in major declines to your aerobic fitness. In Exercise Science this is known as the detraining effect or the principle of reversibility – basically just a fancy way of saying “use it or lose it.”

The rate of decline in aerobic capacity (VO2max) from detraining varies from person to person. Some research has shown that just after training to improve VO2max, one can lose up to half of those gains in just three weeks of being sedentary. However, others may not decline as rapidly.

So what do you do if you’re short on time and/or motivation but really don’t want your aerobic fitness to go down the drain? The key is to just do something.

People make the most rapid gains in fitness when they first begin an exercise program. That is because the body is trained to adapt at the greatest rate when the stimulus (the exercise) is new and unfamiliar. This applies to an entire training program but also to each individual workout.

See, over time, even if we’re just talking about an hour, the stimulus loses its potency. So if you were to do three sets of a particular exercise (and each set is the same intensity), the greatest gains are actually occurring in the first set. Therefore, doing something is MUCH better than doing nothing – in fact, that’s where the rate of gain is at its highest.

Many people do not know that even just 10 minute bouts of exercise can improve/maintain your aerobic fitness. It may not seem like much, but it’s FAR better than doing nothing. Also, keep in mind that as the intensity of exercise becomes higher, the duration can become shorter, since the rate of improvement increases with exercise intensity. Therefore, even a few one-minute high intensity intervals in between short rest periods can be very beneficial.

While many firefighters are granted a workout hour on-duty, these can be interrupted. But even if a call comes in when you’ve only been exercising for 10 minutes, those minutes still count, so that’s no excuse to skip the workout altogether. You can also strategize by making your on-duty workouts short and intense, therefore getting the same benefit of a long, lower intensity workout, while reducing the chance that you’ll be interrupted.

What’s your take on this subject? Have you tried doing 10 minute bouts at a time or high intensity intervals? Let me know in the comments on the blog.

Till next week,
Dr. Karlie Moore