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Condition - Sports Nutrition: A functional perspective

By Christine Bailey MSc PGCE MBANT

Functional Sports Nutrition can provide your athletic clients with a more integrated approach to optimising performance. 

Functional Nutrition is now a well recognised discipline utilised by many practitioners, developed by the Institute of Functional Medicine in the United States(1), by Jeffrey Bland and colleagues. The concept is best illustrated through an interconnected web-like diagram shown (Fig 1). It recognises that not only are different body systems interconnected and interdependent on one another but, when imbalances occur, several areas in the body may be affected. When examining a client, therefore, the focus is on highlighting any imbalances in the body that underlie health conditions observed. Imbalances may arise as a result of environmental inputs such as diet, nutrients, lifestyle and trauma, which are processed by the body, mind and spirit through their unique genetic makeup. How the body responds depends on our genetic bio-individuality and involves physiological processes including digestion, absorption, elimination, detoxification and biotransformation, oxidative stress and energy production, structure and repair of body tissue, immune and hormonal/neurotransmitter processes. For example, it is now acknowledged that imbalances in gastrointestinal (GI) function can influence immune response and subsequently affect inflammation in the body(2). Imbalances in these processes are, in fact, the precursors to the signs and symptoms experienced by the client. The goal of the functional approach, therefore, is to improve balance in inputs and physiological processes, to restore health. As the body moves towards a state of balance, symptoms and health problems are more likely to resolve or lessen in expression, enabling us to function more optimally.

Adopting this approach for athletes is no different than with other clients and, whether they are casual exercisers, weekend warriors or elite athletes, attention will still need to be paid to potential imbalances in all body systems. For athletes, areas which may require particular attention include:

Immunity and inflammation: With high training loads, prolonged exercise intensity, injury and/or poor recovery time, immune cell function can become depressed and inflammation may be systemic(3). Many athletes are still fat-phobic, keeping themselves on restrictive, low-fat diets in the belief that this will help them maintain a low body fat. Along with many other vital functions in the body, the essential fatty acids are involved in immune and inflammatory modulation(4), so increasing levels in athletes’ diets may prove beneficial.   

Oxidative stress/antioxidant requirements: High training levels can increase oxidative stress, increasing antioxidant requirements in athletes. Ensuring sufficient antioxidants can also help protect muscles and connective tissue from free radical damage, important for effective, speedy recovery. If the body’s system is not sufficiently balanced by antioxidant protection, inflammation and tissue degradation may result. 

Energy production and nutritional needs: Energy production, whether aerobically or anaerobically, is dependent on many vitamins and minerals, as cofactors for the energy pathways. These include B vitamins, magnesium, iron and manganese while, for fat metabolism, additional needs include l-carnitine. Poor performance in athletes may mean that there is inadequate intake of these micronutrients or that the body requirements are particularly high and are not being met with current eating patterns. Dietary analysis, coupled with functional testing (e.g. metabolic analysis profiles, amino acids, etc), can help to pinpoint potential inadequacies. 

Athletes in training are also affected by high acid levels (acidosis), as vigorous exercise causes a build-up of lactic acid in the body. An acidic body can result in fatigue, joint pain and muscular stiffness, so switching to an alkaline diet, high in vegetables and fruit, may be beneficial.

Adrenal function: Exercise not only presents an additional stress on the body, it also places increased demands on adrenal function, especially when blood sugar levels are imbalanced and glycogen stores are low. For many athletes, focusing on nourishing the adrenal glands, while stabilising blood sugar through the day, is fundamental to any nutritional programme. The Adrenal Stress Index test can be a useful aid for the practitioner. It is also worth highlighting that the adrenals utilise high levels of B vitamins, vitamin C and magnesium, thus diverting essential micronutrients from energy production and immune support.

Gastrointestinal function: Erratic eating, heavy or prolonged training, mental and physical stress and frequent travelling to events can often result in disturbances in digestive function. Probably one of the most common questions I get asked is: “What should I eat during the day or before a race to avoid gut distress?”

By ensuring optimum digestion and absorption of nutrients with proper timing of meals around training, you can reduce the risk of tummy upsets while maximising metabolic efficiency.    

The concept of individuality 

Central to the functional approach is the concept of the individual’s own biochemical make-up and requirements. Roger Williams, a biochemist, coined the term ‘biochemical individuality’ in the 1950s. Today, approaches such as metabolic typing, nutrigenomics and blood typing are used to help personalise dietary programmes(5). In addition, the Paleo diet approach for athletes is gaining in popularity(6). Previously, general sports nutrition recommendations considered protein needs to be around 1.2g per kg body mass per day, for a moderate training athlete, and up to 1.7g per kg body mass per day for strength and power athletes, or 15-20% of total calories. Carbohydrate needs were fixed at around 50-60% of total daily calories, while fat requirements were fixed at around 25-35%. These broad-brush recommendations do not take into account individual body requirements. Endurance athletes, for example, have a tendency to focus on a high-carbohydrate, low-fat diet, meaning they are more likely to be at risk of protein deficiency as well as missing out on essential fatty acids. By taking a more individualised approach, many athletes are now finding improved performance with increasing protein and healthy fat intake. By tailoring the diet according to the individual’s training programme, you can also help the athlete become more metabolically efficient. This means that the body will be more able to use fat stored at higher intensities of exercise. In turn, this can reduce the reliance on carbohydrates during exercise which, for some, can be responsible for GI distress and blood sugar imbalances. 

It is all too easy for practitioners and athletes to look to the supplement shelf in an attempt to boost performance with ergogenic aids, rather than first establishing functional balance and health in the body. That is not to say that supplements don’t have their place but, without proper daily nutrition, not only will a high level of performance be difficult to sustain, but recovery will take longer and injury and illness will be more likely.

Case Study

Claire, a 55-year-old lady, came to see me, initially to help her lose weight while continuing to train for a half marathon and, later in the year, a marathon. A doctor herself, she was also on thyroid medication for an underactive thyroid. In addition to low energy and difficulty sleeping, she was suffering from digestive complaints, which worsened with stress. Her diet was very regimented, with three meals a day and no snacks and it was high in stimulants, particularly tea and coffee. Breakfast would tend to be porridge and fruit or fruit and yoghurt. Lunch was what was available at the work canteen but typically a low-fat chicken sandwich or soup and a roll. Evening meals were lean chicken or beans and rice followed by fruit and yoghurt. Claire liked a glass of alcohol most nights but was aware of feeling sluggish and hung-over the next morning. 

With a stressful work pattern, combined with a rigid training programme, I was concerned about Claire’s adrenal health and the link to digestive symptoms, in particular difficulty digesting foods, frequent flatulence and constipation, as well as the interrelationship with thyroid function and blood sugar balance. She was complaining of feeling dizzy and light-headed, craving sugary, carb-rich foods and suffering with dry skin and hair. Following a detailed health history, questionnaires and body composition testing, Claire began a new dietary programme, coupled with supplements to support adrenal and thyroid health and digestive function. The new diet was quite a surprise to Claire as it actually contained more food than she was previously eating, with the incorporation of two to three snacks. The focus was on balancing blood sugar through the day, increasing protein and essential fat intake and gradually reducing her reliance upon stimulants like tea, coffee and carbohydrates, particularly grains. She also started to increase her intake of water through the day and switch to herbal teas. We discussed her intake of alcohol and she decided she would try to reduce her intake to weekends only. Within a couple of weeks, Claire noticed her energy levels and sleep patterns were much improved. Previously, she would wake in the night and have difficulty falling asleep; now she was easily sleeping through and waking up feeling refreshed. Digestive health was improving and she was no longer feeling bloated or suffering with constipation. Much to her delight, she had also lost weight. In addition, her percentage body fat had fallen and muscle mass had increased significantly. With improved energy, she began to increase her training intensity in preparation for forthcoming races. 

Over the following months, we continued to tweak her diet, focusing on carbohydrates from fruit and vegetables, rather than grains, plenty of lean protein and healthy fats. Supplemental support included a protein powder, essential fats and additional magnesium, as well as thyroid support. Previously, Claire had been afraid of eating fat and avoided foods like nuts, avocado and oils. Now, they feature in her diet daily. Gradually, over time, her training diet has moved from a carbohydrate, grain-based diet to a Paleo-style diet. Pre-race, she includes a greater range of carbohydrates, including porridge, brown rice, oat cakes and bagels but, for the rest of the time, Claire has found a higher protein/fat diet suits her better and enables her to train at a higher intensity. Claire no longer drinks alcohol as she felt it was affecting her running. Her weight has stabilised, having lost just under one stone, and her muscle mass has increased by 11%. She is now running faster and stronger than ever, recently completing the Brighton marathon in three hours 48 minutes, which was her fastest time to date. She feels she could ‘run even faster’ and is now preparing for a five-day Highland running event.     


Article References

1.The Institute for Functional Medicine: What is Functional Medicine? www.functionalmedicine.org/about 2.Campbell–McBride N. Gut and Pscychology Syndrome. Cambridge UK. Medinform Publishing 2004. 3.Gleeson, M et al. Exercise, Nutrition and Immune Function. Journal of Sport Sciences 2004;22:115–25. 4.Vasquez A. Therapeutic Nutrition and Botanical Medicines for the Promotion of Wellness and Alleviation of Pain and Inflammation. A Detailed Review of Integrative Clinicians. 2005. Biotics Research Corporation. 5.Wolcott & Wolcott. Excellence in Athletes: maximising peak performance through Healthexcel’s System of Metabolic Typing. 2003. Healthexcel Inc. 6. Cordain L, and Friel J. The Paleo Diet For Athletes. 2005 John Wiley and Sons Ltd.

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