Sweating during exercise can cause fluid loss of up to 1 liter an hour, especially in hot humid conditions. Thus, replacing the electrolytes and water lost is especially important to ensure efficient recovery. Murray, et al has shown that a 2% decrease in body weight from fluid loss can be detrimental to performance and that a 2.5% loss of body weight can cause a 15% drop in high intensity exercise lasting longer than 7 minutes. Replacement of elecrolytes (namely sodium and potassium) will help keep blood plasma concentrations balanced and aid in water retention to normalize fluid levels. The problem with many commercial sports drinks (though containing high amounts of sodium and added potassium) is that they are loaded with sugar that can make the stomach upset and feel full following high intensity efforts. Sodium-enriched coconut water on the other hand has been shown to be as effective at replenishing similar amounts of sodium and higher amounts of potassium without the high quantities of sugar that commercial sports drinks contain. Additionally, it caused less nausea and upset stomachs than their sport drink counterparts. So coconut water can be an excellent alternative as your post-exercise recovery drink, especially if you find commercial sports drinks to be too sweet or too hard to drink without feeling nauseous. To read the full article, click here. Enjoy!
Archive for the ‘Nutrition’ Category
I’m gradually getting back in decent running shape. I’ve been training more consistently lately and have been steadily increasing the intensity of my workouts. This morning I did an 11 mile run with 6 miles at tempo, avg. 6:03 pace. Not great, but not bad and something I definitely wouldn’t have been able to handle a month ago. Part of the reason why I have been improving and staying healthy is the attention I have been paying to recovery, nutrition, and ancillary work pre-and post- workouts (for great examples of what I’m talking about, check out Coach Jay Johnson‘s videos). But, for the purpose of this post, I’m choosing to focus on the nutritional aspect with an excellent recovery snack, sugar snap peas and hummus. Why this snack? Because its delicious, I enjoy it, and its chalked full of goodness to help you recover. For starters, snap peas contain decent amounts of 8 vitamins, 7 minerals, dietary fiber, and protein. For instance, in one cup of snap peas, you would consume over 50% of your recommended daily value in vitamin K, over 8g of protein, over 25% in vitamin C, B1, dietary fiber, folate, and manganese, as well as over 12% in vitamin A, B2, B3, B6, magnesium, zinc, iron, and potassium. We know these things are important and good for us, but why and how come following endurance exercise? Vitamin K, for example, is important at helping to maintain bone health. In our bodies, vitamin K gets converted to K2, which activates osteocalcin (a non-collagen protein in bone) that anchors calcium molecules inside bone for adequate mineralization. Additionally, the B vitamins and folic acid help to block accumulation of homocysteine, a by-product that prevents bone collagen cross linkages leading to an inadequate bone matrix and can damage blood vessels leading to athersclerosis. Adequate iron intake is important for endurance athletes, as well, as it is essential for normal blood cell formation and function, to fight fatigue, and for normal immune system activity. So why the hummus with the sugar snap peas? Well again, its delicious and it adds an additional 19g of protein per serving (which helps to rebuild the muscle tissue that was broken down during the workout), and over 50% of your recommended daily folate, dietary fiber, and manganese (important for normal food digestion and bone formation) intakes. Also, it helps to replace some of the sodium (helping to maintain proper electrolyte balance) content lost from sweating, which the sugar snap peas don’t provide. As there are many post-workout snacks that would serve a similar role, this is the one I chose for myself following today’s workout. So I thought I would share its overall goodness to the masses. Enjoy!
A couple of weeks ago, I posted an article on my Twitter account regarding Vitamin C supplementation and its effect on athletic performance. An interesting question was posed on whether the supplement, if spaced out further away from the workout, would have the same effect or whether that negative effect on performance is only caused when taken prior to a workout? I thought I’d explain the mechanism discussed in the research article (can be read here) and discuss the role of Vitamin C, as well as other antioxidants, to determine if supplementation of these are even necessary. Before discussing the article, we have to give a background as to why antioxidants are important during exercise. When running (or doing any endurance exercise for that matter), fatigue will set in because of mitochondrial dysfunction and oxidative stress that occurs as our body tries to adapt to the training stimulus. Our bodies produce ROS (reactive oxidative species or free radicals) in response to exercise. ROS serves as an indicator for our body to produce more mitochondria because this is where oxidative phosphorylation (the process by which your body breaks down consumed oxygen to drive the formation of ATP) occurs. Almost 98% of the oxygen you consume goes through this process, the other 2% gets reduced into a free radical. It is estimated that for every 25 molecules of oxygen the get broken down by normal respiration, 1 free radical gets made. So as oxygen demands increase, the more free radical production is going to increase in a linear fashion creating a balance that the mitochondria can efficiently manage. The body can protect and dispose of free radicals as they are produced using specific endogenous antioxidants such as: mitochondrial superoxide dismutase, glutathione peroxidase, and glutamylcysteine synthetase. This linear balance continues until oxygen consumption exceeds 60% of its max. After this point, ROS production surpasses endogenous antioxidant defense, which can lead to cellular damage in skeletal muscle tissue as free radicals tend to target and react with proteins, nucleic acids, and lipids. This is bad right? Well, that depends. In excess, yes, free radicals are bad as they can lead to serious tissue damage and even cell death. But, free radicals have important training implications as well. When produced during exhaustive exercise, ROS acts as a signal for the body to produce more of the endogenous antioxidants above the level that is normally needed. For example, a 2006 study by Cabrera et al. showed that as the body produced levels of ROS-induced xanthanine oxidase (which can lead to tissue damage), a nuclear protein NF-kappaB was activated. This nuclear protein is one of the main constituents in the pathway the produces more mitochondria. Thus, the ROS production was signaling the body that a greater mitochondria content was needed. This signal allows the body, therefore, to adapt to an intensive training session by stimulating it to increase its amount of cellular mitochondria to handle the stress of future exercise demands. So to get back to the original question of Vitamin C supplementation, why is it bad? If antioxidants help manage the production of free radicals and signal the body that more mitochondria is needed, then supplementation must be good right? Wrong, antioxidant supplementation, specifically vitamin C in this study, do effectively block the production of free radicals. But that doesn’t mean it’s a good thing. By blocking this response, the indicator that the body is getting fatigued either doesn’t happen or becomes delayed. So endogenous antioxidants take longer to respond, meaning less mitochondria production as a result of the training stimulus. This can reduce the effect of a given workout, as the training adaptation will now take longer. So is antioxidant or vitamin C supplementation completely wrong? Not necessarily, I am obviously not suggesting that someone with low levels of endogenous antioxidants would not benefit from supplementation. But for an athlete, who consumes a normal well-balanced diet, exogenous antioxidant supplementation may not be necessary, regardless of when they are taken. Especially when you consider that the daily requirements of vitamin C are around 90 mg in the normal population and 300mg in athletes, where most supplements contain 500-1000mg and can oversaturate the blood. These daily needs are easily achieved eating normal fruits and vegetables (such as peaches, oranges, mangos, strawberries, brocoli, cauliflower, tomatoes, and lettuce).
Gomez-Cabrera MC, Domenech E, Romagnoli M, et al. (2008). Oral administration of vitamin C decreases muscle mitochondrial biogenesis and hampers training-induced adaptations in endurance performance. American Journal of Clinical Nutrition 87, 142-149.
Gomez-Cabrera MC, Domenech E, Viña J. Moderate exercise is an antioxidant: upregulation of antioxidant genes by training. Free Radic Biol Med. 2008;44:126–131.
Ristow M, Zarse K, Oberbach A, Kloting N, Birringer M, Kiehntopf M, Stumvoll M, Kahn CR, Bluher M (2009). Antioxidants prevent health-promoting effects of physical exercise in humans. Proceedings of the National Academy of Sciences of the United States of America 106, 8665-8670.
When recovering from an injury, healing is a complete body process. So to only deal with the musculo-skeletal component of the injury neglects one of the key factors in determining how fast or slow the recovery process will be. Nutrition is key to ensuring that all the systems working together towards “health” are functioning as efficiently as possible. Say you have a car and you neglect to change the oil, fail to put in the required grade of gasoline, or disregard the engine light when it comes on, but you are really diligent about making sure the car is waxed each week, the tires remain in good shape, and the car is covered at night and in bad weather. Then what are you left with? A care that looks nice but is always at the mechanics having problems and doesn’t feel right when you are driving it. Our bodies rely on the fuel we give them to properly operate the systems we need to heal. If we give them junk, they will perform like junk and will constantly be breaking down. This is especially important when we are injured. When an injury occurs, the body’s response is to flush scar tissue and inflammation to the area. Scar tissue binds up the injured area and inflammation protects the area while initiating the healing response by breaking down damaged tissue. Too much of either one though and additional problems may occur. I will talk about too much scar tissue in the next part of this topic, but for now I will address the inflammation aspect. Inflammation is not necessarily bad, as it is our body’s first line of defense against invading bacteria. But, when too much inflammation occurs as a response to injury, healthy tissue can soon become a target. So controlling the inflammatory response, can help accelerate the healing process by preserving the healthy tissue that remains at the site of injury. Classic ways to do this are ice, elevation, and range of motion exercises (passive, active, and isometric contractions), which acts as a pump to rid the area of excess. Nutrition, however, can also play a strong role in controlling the inflammatory response. A number of foods help fight against inflammation, yet there are also foods that can promote its production. Foods that fight the inflammatory response include: fish (such as salmon, tuna, cod, halibut, bass, trout), nuts (such as almonds, walnuts, hazelnuts, flax seed, sunflower seeds), fruits (such as berries, tomatoes, avocados, kiwi, guava, papaya, cherries), green leafy vegetables (like broccoli, spinach, green beans, broccoli sprouts, alfalfa, garlic, cauliflower), spices (like basil, rosemary, parsley, oregano), and some oils ( like avocado oil and olive oil, not heated). Foods that promote inflammation and are wise to avoid when acutely injured include pasteurized dairy products, caffeine, refined sugars (white sugar, brown sugar, corn syrup), red meats, common table salt (best to opt for unprocessed sea salt anyways), alcohol, processed foods, MSG, and artificial sweeteners. Following some of these dietary modifications when injured will help put your body in the best position to heal.
For more information on inflammatory foods, feel free to email me at email@example.com
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