This week I would like to have a closer look at the relationship between training and health. There is no doubt that engaging in regular physical activities improves our health. Exercising increases the production of white blood cells, which are responsible for our immune response to infections. In Poland we have a popular saying “sport to zdrowie”, in English “sport is health”; whilst this is true it is only true up to a certain point. When we increase the duration and intensity of our workouts, our immune system actually gets weaker.
A good study that supports this is one done by Dr David Nieman who is a pioneer in the research area of exercise immunology at Appalachian State University. The study I refer to examined marathon runners at the Los Angeles Marathon in 1987. Dr Nieman himself took part in 58 marathons and noticed that when he ran around 144km a week he more often suffered from throat infections, however when he reduced this distance to below 100km the infections stopped. In examining the impact of marathon training on health Dr Nieman and his team questioned a randomly selected group of 4926 participants of the Los Angeles Marathon. The main interest of this study was history of infections before the marathon and health problems that occurred after the run. The study showed that for a long distance runner the probability of getting an infection is nearly six times greater than people who run lesser distances. Dr Nieman suggests that athletes that run more than 100km a week double their risk of infection. It has been proven that this happens because training hard for long periods (over 1.5 hours) can weaken the immune system, with this affect lasting up to 24 hours. This study was published in the Journal of Applied Sciences, 2007.
Kancho Joko Ninomiya summarised this nicely by saying “Don’t train hard, train smart”. In this way it is recognised that a “good hard session” in the dojo or gym is not always beneficial to our health. It is good sometimes to stop and think about our workout programmes to make sure that we are getting the best out of them.