What is stress? Stress is defined as what you feel when your demands exceed your ability to cope with these demands. Stress has positive and negative effects on the body as short term (acute) stress is essential for survival but long term (chronic) stress is detrimental to health.
The bodies initial response to stress is a flight or fight response activated by the sympathetic nervous system. The heart rate increases, temperature increases and the body mobilises energy reserves as it prepares for a survival situation. The stress hormone cortisol and its partner adrenaline increase and levels of dehydroepianrosterone (DHEA) and testosterone decrease causing a loss in muscle mass and an increase in body fat – particularly around the belly.
Cortisol also works closely with the fat storage hormone insulin. Rising cortisol and insulin levels have been shown to cause fat cells to accommodate more fat, again around the belly area. Moreover, cortisol is also a major stimulus for increasing appetite, therefore the more you stress, the hungrier you get!
How can we control stress? We can provide an outlet for the stress, most commonly through exercise. Exercise increases the production rate of feel good hormones such as dopamine and serotonin which can be as effective as prescription medication for treating symptoms of anxiety and depression. Regular exercise also reverses the effects of poor stress management by its physiological adaptations such as increasing muscle and bone mass, increasing insulin sensitivity and decreasing body fat, resting heart rate and blood pressure.
A regular sleep pattern also helps control stress as it increases serotonin and melatonin levels. Sleep should be 8-9 hours per night with most studies showing between 10pm and 6am as the optimal time to reduce cortisol and stress as much as possible.
Nutritionally, removing stimulants such as caffeine and alcohol, and increasing vitamin C have been shown to be effective. Vitamin C, also known as ascorbic acid, is a water soluble vitamin that helps to strengthen cell membranes. Good sources of vitamin C are citrus fruits, strawberries, tomatoes, broccoli and peppers. Finally, increasing magnesium intake through green leafy vegetables, nuts and fish can reduce physical and emotional stress.
Colin is a freelance Physiologist, writer and speaker who helps runners, beginners to elite, all over the world to reach their running goals. He has spent time in Kenya with some of the world’s best coaches and athletes. A runner himself with a current marathon pb of 2.33.