“Oxidative Stress” may sound like a group of words that belong in a metallurgy class or a chemistry book, but this term is actually very relative to you if you’re participating in CrossFit or any other kind of high-intensity training. Oxidative stress is a phrase we hardly ever use, if ever; instead we typically use words like soreness or exhaustion to describe the same thing.
If you’ve ever found yourself feeling especially slow or tired during a workout- like you have to force those muscles to keep going- you’ve likely experienced the impact of oxidative stress. I’m not talking about the normal feeling of pushing through a tough workout, though, this is more of a response you will feel from your body after several days of continuous training or after completing an especially difficult workout and not allowing your body any time for rest before approaching another WOD.
When we are experiencing the side effects of oxidative stress, we typically tell ourselves “Why am I so sore,” “Maybe I’m working out too hard,” or “I feel like I need to start getting more rest.” While you might be sore under oxidative stress, you may be surprised to find that it is not a result of lactic acid having built up in your muscles. In fact, in many cases of oxidative stress, you may simply feel very tired, or exhausted, without any accompanying soreness. So what causes this lethargic feeling that makes you want to curl up in bed instead of jumping into another workout?
Oxidative stress is a term used to describe the damage that our cells accumulate while using oxygen to produce energy during exercise. Our cells using oxygen to produce energy is called Aerobic respiration. When we exercise, we use more oxygen and so the rate of aerobic respiration increases. Aerobic respiration from exercise can be very taxing on our cells because this process produces free radicals. These free radicals are uncharged molecules that can damage our DNA, make us feel tired, and lead to a host of other problems. Ultimately, free radicals cause damage to our cells and in turn, can interfere with the efficient energy production of our body.
To be clear, all forms of exercise cause some oxidative stress. During the “work” phase, your body is slightly weakened, it later recovers, and becomes more resistant to oxidative stress from the next workout. With more training, your body learns to fight the free radicals produced by oxidative stress by producing its own army of antioxidants. Antioxidants help to control the additional free radicals, generally keeping oxidative stress within safe limits. As your body builds up its own endurance to “oxidative stress” you’ll find that you are able to perform more workouts during a typical week,work under heavier loads, and maybe not require as much recovery time as before. Therefore, oxidative stress is not necessarily dependent on how much you exercise, but how much you do relative to your current ability level. It can also be moderated by adequate sleep, hydration, and allowing our bodies time to rest between workouts.
One last thing we can do help avoid the negative side-effects of oxidative stress is to improve our diet. While our bodies will naturally produce antioxidants to help in the fight against free radicals, a diet rich in supplemental antioxidants can help combat the oxidative stress you incur due to your active lifestyle. Vegetables and fruits are your best sources of antioxidants, but teas such as Green tea and Ginger Tea are also good sources. Some antioxidants occur as vitamins and minerals. Vitamins C, and E are powerful antioxidants as are the minerals selenium and zinc. Minimize your oxidative stress with an antioxidant rich diet, always drink plenty of water, and feel your energy levels rise.