The Fine Line with Exercise

Too much exercise can be bad for your health. There is a fine line between being committed to exercise and being dangerously obsessed: some people literally become addicted to exercise. Those annoyed the gym is closed on New Year's Day, or that they'll miss their 10km run because the relatives are coming over should read on. Over-exercising is hardly a nationwide epidemic. For many, just doing any is a major hurdle. But many amateur aerobic athletes - especially joggers, weekend triathletes and gym junkies actually overtrain, which can lead to burnout, injuries, chronic fatigue and a weakened immune system.

Also, the lifestyle that puts exercise first and family and friends near the back of the pack can become a major source of regret in years to come. Serious exercisers don't like being told they train too much, especially by those who don't train at all. Exercisers and non-exercisers are from different planets. So unless people keep tabs on their own (over)training, they might end up sore, sorry and sedentary. Dr David Pyne, a sports physiologist at the Australian Institute of Sport, says there are four key symptoms of overtraining to monitor:


* Performance, or lack of it. You push yourself up hills but your times keep going downhill.

* Fatigue, but distinguish between the natural and expected daily tiredness from training and the long-term fatigue from over-training which can stretch into days and weeks and which is a cause for concern.

* Psychological changes like getting moody, depressed and experiencing a lack of vigour and motivation.

* Physiological changes like iron deficiency and infections. Because amateur and weekend athletes don't usually have coaches or medical teams to manage them, some actually overdo it more than elite athletes. When symptoms are diagnosed, Pyne says AIS athletes will rest for a day or two, and if there is no change, rest for a week. If things are still the same, it's time for a medical check and blood tests.

Of course, it's better not to overtrain in the first place. Cross-training (doing something different), having regular rest days, and mixing hard and easy days are common strategies. Pyne says that over the past few years rest and recovery has become a major focus at a professional level, and points to the standard Monday night sports story on the TV news - footballers after a big game enjoying a light recovery session in the pool. But some people just don't get it. Sticking to the 'if some is good, more is better' philosophy, some exercisers still think rest is for wimps. American Richard Benyo, in his book The Exercise Fix, recounts the story of a female marathon runner who religiously ran 20 miles every day: 10 miles in the morning and 10 in the afternoon, always the same course. A few years later she couldn't run at all. So if you've been training hard, be kind to yourself and put your feet up this Christmas - that's what holidays are for.