Don’t you love those workouts that leave you feeling like you’re truly on top of the world? That feeling of euphoria and invincibility comes courtesy of “feel-good” neurotransmitters (adrenaline, dopamine and serotonin) that are released during aerobic exercise. These endorphins are particularly effective in getting us through tough workouts and can even mask some of the pain. This can allow you to go longer and harder but might leave you hurting a little later. The truth is endurance athletes and anyone else who exercises at intense levels can be at risk of putting undue stress on their body.
That’s where the power of nutrition steps in!
I recently had an interesting question posed to me: “I often crave citrus fruits after a long run. Am I Vitamin C depleted because of the stress I’m putting on my body?”
I have to admit, I’ve never heard this question before. After a bit of reflection, here are my thoughts:
- My first instinct was that the craving was for sugar….the sweetness of an orange perhaps. Glycogen depletion is responsible for the heavy legs and lack of energy which can occur during sustained efforts of over 90 minutes. Carbs should be topped up before a long run and ingested during the workout to prevent that dreaded bonk. And from what I’ve seen with friends and clients, this is easier said than done.
- My next thought was electrolyte imbalance. Citrus fruits are particularly high in potassium, an important mineral that helps neutralize lactic acid, regulate the body’s fluid absorption rate and prevent muscle cramping or weakening. Dehydration can deplete electrolytes, which could stimulate such a craving.
- Oxidative stress: by-products of energy production during intense or prolonged exercise can generate free radical production, which in turn can induce cell damage to muscles and tissues. While studies have found mixed results, there are some suggestions that Vitamin C can help attenuate some of this damage and aid in muscle recovery. While supplementation may or may not help, eating nutrient rich foods, full of antioxidants, is never a bad idea for general health! Oranges, berries, cantaloupe make fantastic Vitamin C rich post-workout snacks.
- Any time our bodies are under stress the adrenal glands will release cortisol, a hormone that prepares our body for “fight or flight”. Cortisol has both positive (anti-inflammatory) and negative (muscle catabolism) effects. Regular intense exercise exposes your body to increased cortisol levels, which in the long run can cause more harm than good. A 2001 study published in the International Journal of Sports Medicine concluded that Vitamin C supplementation after an ultra-marathon running event was linked to decreased cortisol levels and concluded that Vitamin C could help minimize the damaging effects of excess cortisol. In craving citrus, the body may in fact have been looking for a way to diminish its stress.
This question was so interesting because it raised several pertinent issues with respect to athletes and the demands we place on our bodies. My take home message: enjoy the highs, eat right and pay attention to what your body is telling you. Your intuition is often right.