By Bahram Dideban, MD
We all have moments when our workouts get us down, possibly even enough to stop us going to the gym (insert gasp here). Whatever the cause — too much time at work, an injury, a lack of results, or simply a loss of motivation — once we’ve given up it can be hard to go back, especially since skipping the gym for a lengthy period of time is guaranteed to make those hard-earned gains disappear, right? Maybe not!
During training, the body goes through several changes that increase your maximal oxygen uptake, known as VO2 max. The VO2 max is a measure of how much oxygen an athlete is able to use during exercise and is generally considered to be a measure of an individual’s overall fitness level. An average adult, for example, will have a VO2 max in the range of 35 to 40 ml/kg/min for a male and 27 to 31 ml/kg/min for a female, while a professional runner, by comparison, can have a VO2 max as high as 85 ml/kg/min and a cyclist as high as 95 ml/kg/min.
Why Your VO2 Max Matters
Exercising increases VO2 max, meaning that, like a well-oiled machine, a trained athlete is able to deliver more oxygen to his or her muscles and convert it to useful energy. During detraining, several things happen that lead to a lowered VO2 max. First, the body begins to retain less water, which in turn lowers the volume of blood in the body. This isn’t a dangerous (or even very noticeable) change in blood volume, but it does result in less blood being pumped out of the heart with each heartbeat (i.e. stroke volume). Since oxygen is carried within the blood, a lower stroke volume means less oxygen is being shuttled to the muscles, ultimately causing a decrease in VO2 max.
Pick Up Where You Left Off
In fact, a classic study published in the Journal of Applied Physiology showed that during the first 21 days following detraining, VO2 max dropped by about seven per cent. After 56 days, VO2 max had dropped by an average 16 per cent when compared to the levels of regularly training subjects. That being said, after 84 days (that’s almost three months), participants with a reduced VO2 max still had higher levels than subjects who had never trained. This means, generally speaking, you will continue to sustain some of your gains for lengthy periods of time, even if you stop training. That’s your first reason for not losing hope and getting back in the gym.
But it’s by no means your last. Another classic Journal of Applied Physiology study showed that even following 30 to 32 weeks of detraining, subjects were able to return to their original levels of strength following a retraining period as short as six weeks. The same study also found that although the composition of the fibres in the muscle tissue changed, the overall cross-sectional area of the muscle is retained over a 30- to 32-week detraining period — meaning even your muscles are waiting for you to pick back up at the gym.
Now the real question is, if you do have to cut down on time in your gym schedule, is it still possible to make the same gains? The short answer is “yes.” Try upping your intensity on the days you are able to train; a short but explosive workout is best. A British Journal of Sports Medicine study found that subjects who previously trained at lower intensities (55 per cent of their one-rep max) lost all their gains during a four- to eight-month detraining period, whereas those who exercised at higher intensities (82 per cent) were able to retain all of their gains in the same period.
Another study from the Journal of Strength & Conditioning Research also found support for high-intensity training. After 24 weeks of a standardized exercise regimen, elderly subjects took a 24-week period of detraining, with no exercise at all. During the detraining period, all subjects showed significant losses in strength and flexibility, but those subjects who exercised at a high intensity (80 per cent of their one-rep max) showed much lower losses — meaning that more intense workouts, even if they occur less often, can be more beneficial. So what are you waiting for? Make a gym comeback today to reap the rewards of your past, present, and future!