Muscle Talk

CrossFit has become one of the most popular forms of exercise over the past several years, and for good reason¬—it’s fun, it’s challenging, and it delivers great results. CrossFit workouts involve a variety of high-intensity and functional types of exercise, including Olympic weight lifting, kettlebells, plyometrics, intervals, and calisthenics. The body primarily uses two energy systems to generate power and fuel intense CrossFit workouts: phosphagen and glycolitic. The phosphagen system provides the majority of energy used for short bursts of high-intensity activities, which usually last 10 seconds or less. The glycolytic system delivers energy for moderate-intensity activities, which generally last 30 seconds to two minutes. The phosphagen and glycolytic systems are collectively known as the anaerobic energy system because they don’t require oxygen to generate energy. The third energy system, called oxidative or aerobic, provides energy for low-intensity, long-duration exercise, and is therefore the least important during CrossFit exercise. When it comes to supplementation for CrossFit performance, it makes sense to focus on using supplements that support the phosphagen and glycolytic energy systems. So here are my top five supplements for CrossFit athletes!

CREATINE
Creatine is a no-brainer for CrossFit athletes. It’s the most effective supplement on the planet for enhancing high-intensity exercise performance. Creatine plays a key role in the body’s phosphagen energy system and helps recycle ATP faster for greater power, strength, and recovery between bouts of exercise. After it’s ingested, creatine acts as an energy and pH buffer during intense exercise. Creatine kinase catalyzes a reaction between free creatine and phosphate ions (from the breakdown of ATP to ADP), resulting in phosphocreatine (PCr), which is then locked into the muscle cell due to its strong negative charge. PCr then reacts with ADP to form more ATP during exercise. All of this results in more energy and faster recovery between bouts of high-intensity exercise!

CARBOHYDRATE POWDERS
Carbohydrate powders are often overlooked, but one could easily argue that they’re the most effective and essential supplement for CrossFit athletes. As I already explained, the phosphagen and glycolytic energy systems are dominant during CrossFit workouts. Creatine addresses the needs of the phosphagen system, while carbohydrates do the same for the glycolytic system. Once ATP is gone, the body will start to access stored glycogen (i.e., stored carbs) as well as available glucose to start generating more ATP. Because CrossFit workouts are intense and require a lot of energy, supplementing with carbs before and during them can help keep glucose readily available for immediate use by your muscles, allowing you to keep your intensity cranked! Supplementing post-workout also helps to replenish lost muscle glycogen, loading the muscles up for the next workout. High-molecular weight (HMW) starchy carbs are my preferred carb source. These types of carbs have low osmolarity and allow for the quickest transit time and fastest digestion.

BRANCHED-CHAIN AMINO ACIDS (BCAAs)
BCAAs can improve power and performance in two different ways; first of all, they have a glycogen-sparing effect during exercise and can support the glycolytic energy system. In fact, research shows that BCAAs spare muscle and liver glycogen stores, and increase fuel supply to working muscles during exercise. The other way that BCAA supplementation can improve performance is by preventing central nervous system (CNS) fatigue during intense exercise.

CITRULLINE MALATE
Citrulline is a popular nitric oxide (NO) pump ingredient, and for more info on that, check out my “Science Behind the Pump” article on page XX of this issue. In addition to its incredible pump properties, citrulline (and more specifically citrulline malate) also delivers great performance-enhancing benefits. Citrulline plays a role in ATP production when energy demand increases. It also helps buffer the buildup of ammonia in muscle, which reduces exercise fatigue and increases workout endurance! Two main types of citrulline are used in sports supplements: citrulline malate (CM) and L-citrulline. CM is citrulline attached to a molecule of malic acid. The best form of CM comes in a ratio of 2:1 (two molecules of citrulline to one molecule of malic acid). Based on the body of research conducted on citrulline and CM, it appears that CM is more effective in producing improvements in exercise performance (i.e., endurance, strength, etc). Citrulline has an impact on both the phosphagen and glycolytic energy systems. It can modulate enzymes involved in glycogen breakdown, glycogenolysis, and enzymes that convert glucose to ATP (glycolysis). This action shifts muscle from aerobic to anaerobic metabolism and reduces the rate at which the body uses up ATP and phosphocreatine. This means more energy is available to the muscles for longer periods of time!

BETA-ALANINE
Beta-alanine is a very popular supplement with many athletes because of its ability to buffer acidic waste product in muscle during intense exercise. When beta-alanine is used as a supplement, it’s taken up by your muscles, and together with histidine, is resynthesized into carnosine by an enzyme called carnosine synthetase. An increase in intramuscular carnosine levels can increase the buffering capacity of a muscle. By increasing the buffering capacity of muscle, beta-alanine supplementation can result in a delay in muscle fatigue and failure, and considerable improvements in muscular strength and endurance. Although beta-alanine has solid research backing its efficacy, it’s never been one of my favorite supplements because of the tingling effect it has on the skin. I’ve tried the time-released versions of beta-alanine, but I didn’t find they work quite as well. That being said, many other people get great results from using beta-alanine, so it’s worth a try! See how it works on your body!

To learn more about Crossfit as a sport, check out our article on Crossfit VS Bodybuilding here!