Choline
Choline Present in all living cells, choline is another B-complex vitamin. It is synthesized from two amino acids, methionine and serine, with help from vitamin B12 and folic acid. Choline works with inositol, another lipotropic dietary factor, to prevent fat from building up in the liver and to shuttle fat into cells to be burned for energy. Choline is involved in the formation of the neurotransmitter acetylcholine in the body. If acetylcholine is reduced in the nervous system, fatigue may set in. Because acetylcholine is the most abundant neurotransmitter in the body, acting every time we think or move, it’s not surprising that low levels would lead to fatigue. Additionally, choline plays a central role in many other physiological pathways, including the cell membrane signaling involved in brain function and the methyl-group metabolism involved in hormone and energy metabolism. Researchers at MIT studied runners before and after the Boston Marathon and found a 40 percent drop in their plasma choline concentrations. They don’t know why this happened; however, they speculated that choline is used up during exercise to produce acetylcholine. Once choline is depleted, there’s a corresponding drop in acetylcholine production, and when production falls off, the ability to do muscular work falls off. A 2008 review published in the International Journal of Sport Nutrition and Exercise Metabolism pointed out that strenuous and prolonged physical activity may decrease circulating choline stores. Supplementing with choline prevents this, and may even improve endurance. The longer and harder you train, the more choline you use, and possibly use up. Choline is best absorbed when taken as phosphatidylcholine (PC), which is the body’s natural reservoir of choline and is also available as a supplement. PC is the major building block for all cell membranes, and it supports cell, tissue, and organ functions. Supplementing with PC helps maintain sufficient choline reserves for good health. You can also boost absorption by taking PC with phosphatidylserine (PS), another key building block for cell membranes. PS dietary supplements also may help you improve your athletic performance by suppressing cortisol, a potent, catabolic (breakdown) stress hormone. Too much cortisol in the body, which can result from intense workouts, may have negative effects on your training, performance, and physique. Research has shown that short-term oral supplementation of 750 milligrams per day of phosphatidylserine for 10 days improves exercise capacity during high-intensity cycling and increases running performance. Supplementing with PS is a natural, drug-free choice for athletes who want to overcome the effects of exercise-induced stress. Most vitamin supplements contain choline, and you should make sure to consume at least the DRI for choline daily. The effective dosage in sport studies is 0.2 gram of phosphatidylcholine per kilogram of body mass. This does not need to be any kind of loading strategy but can just be a maintenance program. The effective dosages for phosphatidylserine in exercise studies range from 300 to 800 milligrams per day for 10 to 15 days.
- Published in Blog, Nutrition, supplements
Vitamin C
Vitamin C, or ascorbic acid, is a nutrient that can be synthesized by many animals but not by humans. It’s an essential com- ponent of our diets and functions primarily in the formation of connective tissue such as collagen. Vitamin C is also involved in immunity, wound healing, and allergic responses. As an antioxidant, vitamin C keeps free radicals from destroying the outermost layers of cells. When paired with a plant-based iron source, vitamin C enhances the absorption of this hard- to-absorb form of nonheme iron. Adding lemon juice to your spinach can give a better boost to your iron stores.
If you work out regularly or train for ath- letic competition, you know that a cold or respiratory infection can sideline you pretty fast. Fortunately, researchers have found that supplementing with 500 milligrams daily of vitamin C appears to cut the risk of upper respiratory tract infections. This benefit may be due to the antioxidant effect of vitamin C or to its overall immune-boosting capability.
Supplementing with vitamin C will improve your performance but only if you are deficient in this nutrient. Supplementation does not enhance performance if you already eat a healthy, nourishing diet that is high in citrus fruits (which are high in vitamin C) and other fruits and vegetables. In fact, a review of 12 studies showed that in 4 of those studies, daily doses of 1 gram (1000 mg) of vitamin C may lead to decrements in performance. The conclusion of the authors was that consuming vitamin C at levels that are naturally found in foods every day (250 mg) is best for supporting training effects and athletic performance.
My recommendation is that you should first and foremost make plant foods, which are often naturally high in vitamin C, the mainstay of your diet, ensuring a vitamin C–rich diet. During cold and flu season you might experiment with supplementation if you don’t consume at least 500 milligrams of vitamin C in food alone. If you choose to supplement, stay below 1 gram (1000 mg) daily in food and supplements.
- Published in Blog, Nutrition, supplements
HMB
Effects of HMB Supplementation
Nissen et al conducted one of the first studies addressing the effects of oral supplementation with different doses of HMB. Individuals were supplemented with 0, 0.5, and 3.0 g/day of HMB in conjunction with a resistance training program for 3 weeks. In the first 2 weeks urinary excretion of 3-methyl-histidine was decreased, indicating an attenuation of muscle proteolysis, and at the end of the protocol the muscle damage indicators—CK and lactate dehydrogenase (LDH) activities—were lower in the supplemented group. A significant increase in fat-free mass and strength was reported when 3.0 g/day of HMB was supplemented in association with resistance training for 7 weeks. However, controversial results have been reported in studies with humans assessing the effects of oral supplementation of HMB in tandem with resistance training . In previously untrained individuals, HMB supplementation (3.0 g HMB per day) during a resistance training program did not change the body composition, muscular strength levels, and biochemical markers of protein turnover and muscle damage, increased muscle mass or potentiated the strength gain and fat-free mass gain in elderly subjects. In addition, in athletes highly conditioned to resistance training, HMB was unable to promote gains in strength and fat-free mass in water polo, rowing, or football athletes and did not elicit attenuation of muscle damage markers (Creatine Kinase [CPK] and LDH) and gains in speed.
In untrained individuals oral supplementation of HMB in association with resistance training may elicit gains in strength and muscle mass because these effects appear to be more prominent among those who are in the initial phase of training. Untrained individuals submitted to a resistance training program exhibit lower levels of muscle damage markers when supplemented with 3.0 g/day of HMB. If HMB reduces the muscle protein catabolism associated with exercise, resistance-trained athletes may not respond to HMB supplementation in the same manner as untrained individuals, due to training-induced suppression of protein breakdown. To confirm the anticatabolic properties of HMB, further research using more precise techniques is required because most studies addressing this issue have used the urinary excretion of 3-methyl-histidine as an indicator of muscle catabolism, and this technique has been criticized.
It has been demonstrated that ingestion of 3.0 g/day of HMB increases its plasma levels and promotes gains in fat-free mass and peak isometric torque during a resistance training program. Greater amounts of HMB (6.0 g/day) did not elicit the same effect. Furthermore, 8 weeks of HMB supplementation (up to 76 mg/kg/day) appears to be safe and does not alter or adversely affect hematological parameters and hepatic and renal function in young male adults.
Mechanisms of Action
Based on studies evaluating the mechanisms of action of HMB, it is postulated that such supplementation could involve the following mechanisms:
(1) increased sarcolemmal integrity
(2) increased metabolic efficiency
(3) upregulation of IGF-1 expression in liver and skeletal muscle
(4) stimulation of protein synthesis by increasing the mTOR signaling pathway, and
(5) suppression of proteolysis by the inhibition of the ubiquitin-proteasome system.
The protective effect of HMB against contractile activity–induced damage may be associated to increased stability of muscle plasma membrane. HMB is converted to b-methylglutaryl-CoA (HMG-CoA) for cholesterol synthesis, and inhibition of HMG-CoA reductase affect the electrical properties of cell membrane in skeletal muscle. In addition, HMB supplementation may also promote an increase in acetyl-CoA content through the conversion of HMG-CoA into acetoacetyl-CoA by HMG-CoA synthase in mitochondria, increasing metabolic efficiency. HMB supplementation has also been reported to stimulate lipolysis in adipose tissue and increase fatty acid oxidation capacity of skeletal muscles. One other mechanism underlying the effects of HMB supplementation is the increased expression of IGF-1 expression in liver and skeletal muscles. Kornasio et al. demonstrated in vitro that HMB could stimulate IGF-1 expression, as well myogenic regulatory factors and thymidine incorporation (an indicator of DNA synthesis). Later Gerlinger-Romero et al. demonstrated that supplementation with HMB promoted an increased GH and IGF-1 expression in pituitary and liver, respectively. In vivo and in vitro animal data also pointed to a possible role of HMB in stimulation of mTOR signaling pathway and inhibition of ubiquitin-proteasome system, a proteolytic system involved in skeletal muscle atrophy. More studies are needed to determine whether the actions of HMB on protein synthesis and degradation signaling pathways are direct or mediated by an increased expression of IGF-1, as well to determine the molecular basis of HMB supplementation in humans.
Conclusions
In the recent years, the growing interest in HMB supplementation has arisen from previous demonstrations of its effects on fat-free mass and strength gains in combination with resistance exercise, its anticatabolic properties, and speculations related to the mechanisms of action involved. Most studies have used 3 g/day of HMB, grounded in evidence that this dose produces better results than 1.5 g/day and is equivalent to 6 g/day. If in untrained individuals HMB supplementation appears to act as an effective ergogenic, in well-trained individuals and athletes the positive effects of HMB are less clear. The physiological mechanisms involved increased sarcolemmal integrity and metabolic efficiency, stimulation of GH–IGF-1 axis, stimulation of protein synthesis, and suppression of proteolysis. Although some of these mechanisms were demonstrated in animal and in vitro studies, human studies are needed and could provide new insights into the mechanisms underlying the effects of supplementation.
- Published in Blog, supplements
Whey Protein
Whey and casein are two of the most popular protein supplements on the market, and for good reason. They’re both high-quality, highly bioavailable, complete proteins that are particularly rich in branched-chain amino acids (BCAAs), which makes them great for muscle growth and repair.
However, despite both coming from milk, there are distinct differences between these muscle-building brothers.
Both whey and casein are dairy-based proteins derived from the cheese-making process. In fact, all dairy products contain a blend of both whey and casein. Milk is roughly 80 percent casein and 20 percent whey.
How Do Whey And Casein Work?
Whey protein is known as the “fast” brother because it’s rapidly digested. Casein protein, on the other hand, is the “slow” brother because it’s gradually digested.
Although both bros in this protein pair have a high amino acid content, whey is considered to be the more anabolic (muscle-building) milk protein because of its ability to rapidly spike blood amino acid levels, which are necessary to kick-start muscle protein synthesis.
Casein, on the other hand, is often considered to be an anticatabolic, or muscle-sparing protein, because it provides a steady stream of amino acids over time that keeps muscle tissue breakdown at bay.
For muscle growth to happen, protein synthesis needs to be greater than muscle breakdown. Since whey increases protein synthesis and casein prevents muscle breakdown, both proteins, taken strategically, can help you build muscle.
Whey Protein
Whey protein takes only 20 minutes to be digested, absorbed into the blood, taken up by bodily tissues, and metabolized. Within an hour, it will have been used up for either protein synthesis or oxidation. This is amazingly fast in comparison to casein, or even dietary protein from whole food.
It is this sudden increase of amino acids that stimulates muscle protein synthesis. Whey quickly tips the balance from muscle breakdown to protein synthesis to get you out of a catabolic state, like you get from lifting weights.
Casein Protein
When you consume casein, you will reach a peak in blood amino acids and protein synthesis between 3-4 hours. This peak, however, does not even come close to that of whey.
But this, too, is a good thing. Even though casein doesn’t raise your amino acids as high, it dramatically slows the rate of protein breakdown, protecting your existing muscles.
When To Take Which Protein
The quick-digesting nature of whey protein makes it excellent before, during, or after your workouts, because it will fuel your muscles quickly with minimal GI distress (unless you have trouble digesting milk, in which case you should definitely avoid dairy proteins).
Casein, on the other hand, is best used before fasting, such as before bed or a long day of nonstop meetings, because the slow release of amino acids promotes fullness. It also can be added to meals.
Slow digestion can be a negative before or after training when you are trying to get amino acids into the system quickly, but it’s a benefit when it comes to holding off hunger and catabolism when you’re gunning for fat loss.
Mixing Whey And Casein
Some people also like to pair whey and casein together post-workout. The idea is you’ll get both rapid and sustained amino acids this way.
However, others believe mixing the two protein powders blunts the amino acid spike from whey, and slows its absorption. Try it both ways to learn what works best for your body. The most important thing is making sure you get plenty of amino acids, period.
Amino Acids In Protein Powders
When protein products start touting how much of a certain amino acid they have added or that they have a better amino acid profile, ignore the hype. It doesn’t matter. The amino acid profile becomes important when you are comparing different protein sources. And since both casein and whey are milk-derived, they have essentially the same amino acid profile.
How To Use Whey And Casein Protein Powders
Whey protein powder is extremely versatile: It mixes beautifully with water or milk, but also pairs well with oats, Greek yogurt, peanut butter, or your favorite protein shake. If you like baking, try one of the many whey-protein-powered recipes in our Healthy Recipe Database.
Casein protein makes for an excellent bedtime snack. Simply mix it with a splash of water or milk to make casein pudding, add it to some Greek yogurt (which is a fantastic source of casein on its own), or make a slightly fancier snack with these delectable before-bed recipes made with a whey and casein mix.
Research On Casein And Whey
A study looked at healthy subjects with a normal protein intake. They fasted for 10 hours, then were either given 30 grams of whey protein or 30 grams of casein protein.
Blood leucine levels peaked one hour after ingestion of whey or casein. However, the whey protein group peaked at higher levels and returned to baseline after four hours. The casein protein group peaked at a lower level but didn’t return to baseline until seven hours later.
Whey protein enhanced protein synthesis by 68 percent, but did not affect protein degradation. Casein decreased protein degradation by 34 percent, but did not affect protein synthesis.
The study points out the benefits of both proteins as we mentioned earlier. Keep in mind that a mixed protein meal (as opposed to supplementation with a single protein) would have a different absorption rate that might change the effects on protein synthesis and breakdown.
With the information from the study above, we can question the common recommendation to eat every three hours to avoid losing muscle. By taking a protein supplement, especially casein, you can keep your amino acid levels elevated for much longer between meals.
Interestingly, a different study concluded that taking either kind of milk protein after exercise resulted in similar increases (no significant differences) in muscle protein net balance, resulting in net muscle protein synthesis despite different patterns of blood amino acid responses.
This suggests that while it’s preferable to take whey protein around workouts and casein around fasting periods, the most important thing is getting enough protein in general, whether from whey, casein, plant-based protein powder, or any other protein source.
Wrapping Up
In summary, casein is a slow-digesting protein that is anti-catabolic: It prevents excessive protein breakdown. Whey protein is a fast-acting protein that is anabolic: It stimulates protein synthesis, but does not inhibit catabolism. You can encourage anabolism and discourage catabolism by including both whey and casein in your diet.
- Published in Blog, supplements