With any serious commentary about any topic, it is important to know what the words you are using actually mean.
People often use the terms ‘fitness’ and ‘health’ synonymously, but they are not the same thing. And it is easy to mistakenly assume that one will automatically lead to the other.
Obviously there is a link between fitness and health. If you do no exercise at the moment, then a little of almost any exercise will make you fitter and this will likely make you healthier.
At this point let’s define our terms. It is amazing how many people, health professionals included, use these terms in very vague and imprecise ways. So here are the definitions that I am using; taken principally from Dr. McDuff and Dr. Little in their book ‘Body by Science’.
HEALTH. A physiological state in which there is an absence of disease or pathology and that maintains the necessary biologic balance between the catabolic and anabolic state.
FITNESS. The bodily state of being physiologically capable of handling challenges that exist above a resting threshold of activity.
EXERCISE. Exercise is a specific activity that stimulates a positive physiological adaptation that enhances fitness.
I hear people say things like, “I don’t need to do more exercise I already walk a couple of miles a day to and from work and play a sport at the week end.” This is merely physical activity, which is not necessarily exercise!
Exercise, according this definition, has to push your limit, not merely operate within it. Your body will respond to what you ask of it. If you ask your body to perform at fitness level A, which it is already capable of, then it will oblige by continuing to remain at fitness level A. However, if you push yourself beyond A to the point of failure, the point where your body is unable to do what you ask of it, it will respond by adapting (or trying to) to be able to do what you asked. You will become able to do A+. This is exercise.
Now we need to look at optimisation of exercise and understand practically why health and fitness are different.
If I do an exercise to failure so that my body responds, will it respond more if I do that exercise again? Simply put – no.
There have been a number studies comparing groups doing the same set of exercises for varying numbers of times. For example, one group might do a set of squats to failure once a week, while another group, rests for a short time then does a second set, and another group does a third. In all cases there has been no significant increased performance with increased sets. It seems our bodies are smart enough to get the message that an adaption is called for the first time. Will an hour per week of just bicep work with a dozen different exercises and multiple set of each, all aimed at that one muscle work? Of course, but it seems that so would one set of one exercise (done right) also work as well. The difference is that the hour felt like it would work better; made you feel dedicated so you deserved great results, and put so much wear and tear on your joints that you are on the road to all sorts of joint problems sooner or later. In other words, you have sacrificed your health to gain no extra fitness. Any activity that is highly repetitive has wear and tear consequences that will sooner or later override the body’s ability to recover and repair itself. To put it another way, if I send you a message requesting you do something once, if you get the message and are willing to do what I request, the job is done. If I send you the same message 50 times, you aren’t going to do what I asked any more than you were after the first message; though you might get a bit pissed off with my asking. And so will your body!
So, what is the optimum level? The exercise that will see us make steady progress in fitness, that only enhances our health. The level that produces only an improvement without any negative results.
A number of studies have shown that a short intense effort (sprinting) has a massive impact of stamina. In one example one group performed short bursts of ‘flat out’ activity for 30 seconds, repeated a few times with a couple of minutes recovery, done 3 times a week. After only 2 weeks this produced up to a doubling of aerobic fitness. (A measured increase of 38% in the activity of the mitochondrial enzyme citrate synthase)
Another group exercised for 90-120 minutes at 65% of flat out, 3 times a week, also for 2 weeks. This group had similar increase in endurance, but no more. They however did have a massive increase in damage to joints and injury risk. Not to mention the huge amount of lost time and the decreased chance that they would maintain this level of commitment over any length of time.
So in terms of muscle enzymes (essential for preventing type two diabetes) overall fitness including heart and lungs. You could train for six hours per week (with massive increase in wear and tear) or six minutes a week.
Incidentally it doesn’t matter if your short bursts of flat-out effort are done rowing, cycling, running or on a punch bag. When the study director was asked if one could get the same results with even less training sessions, like once a week, he basic said, probably yes.