Improve you performance with London sports nutritionist
We all know that exercise is good for us, some people like to go for a walk or dance, some people go to the gym to lift weights, others like to get out and pound the road with a run. Essentially any form of exercise has its health benefits; perhaps the most beneficial aspect of exercise is that it helps to maintain our weight by building and using our muscles and burning calories and daily human movement is essential for this. But as we seem to be living in a world with an expanding waistline, where 1 billion people are now classified as overweight, and we are working in sedentary jobs and are exposed to more stress than ever before do we all need to be exercising more? Well perhaps we do, but exercise can also have deleterious effects if it is not used correctly.
One deleterious side effect of exercise that has been highlighted in the press recently is the rise in sudden death syndrome whilst exercising. Because we know that exercise helps weight management we now have many overweight and obese children and adults undertaking unsupervised and unguided exercise. It is not just the overweight who are at risk – considering the number of footballers and other athletes who have died recently from sudden heart attacks – perhaps the most recent and thankfully happy outcome was that of Fabrice Muamba that will jog the memory.
So we have established there are many positive and negative effects that occur in our body with exercise. One system that exercise affects is the immune system and it has long been observed that exercise affects the immune system in a dose dependent way – a phenomenon known as hormesis. This is where a low dose exposure to regular exercise has a positive effect on our immune system, but whereby a high dose exposure has a negative effect.
In real terms regular bouts of exercise reduces the severity and occurrence of illness for some, however it has been observed that in others, particularly endurance athletes, prolonged exercise and intensified training can evoke a decrease in the immune system and lead to cold and flu like symptoms and fatigue.
The human immune system is an extremely complex system that comprises a variety of cells and actions. One function of the immune system is to release antibodies. These antibodies are responsible for binding bugs and germs and destroying them before they make us sick. One antibody that has received a lot of research attention is secretory IgA (SIgA). Its major effect or function is to provide the ‘first line of defence’ against pathogens in the respiratory and gastrointestinal tracts as described by Walsh and his colleagues in their 2011 position statement on exercise and immunity. When these bugs are inhaled or ingested the SIgA antibodies that reside in the mucus secretions lining the gut and airways seek out, attach and destroy these bugs before they can infect us.
It has been observed that with prolonged or repeated intense exercise levels of SIgA decrease and the bugs that we come into contact with can now infect us. This is linked to an increase in the occurrence of upper respiratory tract infections (URTI’s) such as sore throats, colds and flu, that one would assume correlates with a suppressed immune system.
Thomas Burford and Stephen Rossi in their position statement for the National Strength and Conditioning Association describe something known as the “open window theory” where it is believed that following strenuous exercise there is a 3-72 hour window that exists in which immune function is compromised, the most often reported factors that occur in this window are decreased SIgA levels leading to a sore throat, cold and flu like symptoms. It was scientifically demonstrated nearly three decades ago that exercise affects the immune system. A group of Scandinavian researchers reported in 1982 that SIgA levels were lower in elite cross-country skiers compared with recreational athletes and that the levels were further lowered after a competitive race and were believed to reflect the chronic suppression of the immune system.
The good news is that the recovery of the immune system after single bouts of exercise has been reported to occur within one hour. So if you are going to the gym 2 to 3 times a week, exercising for an hour your immune system is probably recovering well be each subsequent bout of exercise.
However, recovery of the immune system and SIgA levels may be delayed or even chronically suppressed after both exhaustive exercise and repetitive intense training, so if you exercise excessively, are training for a marathon or triathlon or are a professional athlete there is a greater risk that you can get ill.
London sports nutritionist monitoring SIgA
Monitoring of SIgA with the help of a London sports nutritionist may be a useful tool for determining the risk of infection in elite athletes and devices are available to collect saliva samples and test the levels of your antibodies. But most people don’t have access to these tools and thus need other strategies to monitor and protect their immune systems.
We also need to remember that we live in a stressful world of traffic congestion, e-mails, mobile phones and work deadlines etc… We know that stress lowers SIgA and immunity. I’m sure you all have either experienced or know someone who got ill after a prolonged stressful life experience. And this is acknowledged by Walsh and his colleagues in their in their 2011 Position Statement: Maintaining Immune Health describing training load manipulation, nutritional intervention, sleep and stress reduction as being the major components of supporting immune health.
So we know that exercise in small doses is healthy, but what do we need to do if we have to / like to exercise daily or are stressed or use exercise and a stress management tool.
London sports nutritionist intervention
Working with a London sports nutritionist can help you overcome illness associated with exercise. Eating a diet low in sugar and rich in antioxidants, amino acids and essential fats is generally considered to be immune-supportive. But in reality what does this mean and what would it look like? Well, generally eating meat, fish or seafood at main meals with vegetables, whole grains and salads with fruits and nuts and / or seeds as snacks is a good place to start.
Beyond this the role of certain vitamins, minerals, herbs and amino acids and believed to play an additional role.
However there is some contention in the scientific literature as to whether using such supplements blocks the transient immune changes, oxidative stress and inflammation that follows exercise that hinders the bodies adaptation to exercise or whether the supplements do not completely block the deleterious effects of exercise, allowing adaptation to occur, but partly blocking the immune changes, oxidative stress and inflammation allowing for a quicker recovery.
Either way Walsh and his research group show us that carbohydrate ingestion before, during and after exercise reduces the proliferation of certain immune cells and stress hormones, but has little effect on SIgA. Thus using carbohydrate containing beverages before, during and after exercise, preferably good quality drinks that also contain antioxidants such as Vitacoco, Cherry Active or Go Coco rather than commercial sports drinks, would be the best intervention to have an effect on the immune system.
London sports nutritionist supplements
The Walsh group go on to suggest that research on individual nutrients associated with immune health in athletes such as vitamin C, glutamine, probiotics, echinacea and omega 3 are either not recommended or don’t have enough research to support use. But I think it is important to point out that research is usually always behind what happens in clinical practice – just because there is currently not enough research to support doing something that we observe is useful doesn’t mean we should stop doing it. And the whole research process sometimes doesn’t lend itself well to establishing how well these nutrients and especially combinations of these nutrients work in clinical practice. However, Walsh and his colleagues do concede that a mixture of these nutrients will probably perform better than individual supplements in supporting the immune system especially in the presence of carbohydrate beverages and vitamin D, which itself plays a huge role in the human immune system. So using these vitamins to support your immune system and protect your SIgA levels from dropping is worth considering.
One nutrient that Walsh and his colleagues do recommend is quercitin as in-vitro studies have shown strong anti-inflammatory, anti-oxidative and anti pathogenic effects. They go on to state that quercitin should be used in conjunction with other flavanoids and nutrients that possess anti-inflammatory and anti-oxidative effects such as green tea and omega 3 fatty acids (and possibly also vitamin C, zinc, vitamin E and beta carotene). Quercitin is found in apples, grapes, berries, onions and tea so be sure to include these in your diet and adding a 1000mg extract may also be a good idea to support your immune system.
Burford T. W. and Rossi. S. J. Exercise and immune function. A presented as part of the NSCA Hot Topic Series.
Tomasi TB, Trudeau FB, Czerwinski D, Erredge S. Immune parameters in athletes before and after strenuous exercise. J. Clin. Immunol. 1982; 2: 173–8.
Walsh, N. P. Gleeson, M. Shephard, R. J. Gleeson, M. Woods, J. A. Bishop, N. C. Fleshner, M. Green, C. Pedersen, B. K. Hoffman-Goetz, L. Rogers, C. J. Northoff, H. Abbasi, A. and Simon, P (2011). Position Statement Part one: Immune function and exercise. Exerc Immunol Rev. 17: 6 – 63.
Walsh, N. P. Gleeson, M. Shephard, R. J. Gleeson, M. Woods, J. A. Bishop, N. C. Fleshner, M. Green, C. Pedersen, B. K. Hoffman-Goetz, L. Rogers, C. J. Northoff, H. Abbasi, A. and Simon, P (2011). Position Statement Part two: Maintaining immune health. Exerc Immunol Rev.17: 64 – 103.
London sports nutritionist Steve Hines.