One rat study that compared male and female rats and used a forced swim test (as a measure of serotonergic activity of anti-depressants[227]) found that a sexual dimorphism existed, and females exerted a serotonin-mediated anti-depressant response while male rats did not.[228] It appears that these anti-depressive effects are mediated via the 5-HT1A subset of serotonin receptors, as the antidepressant effects can be abolished by 5-HT1A inhibitors.[229]
Related to exercise and fitness, BCAAs are taken to help reduce muscle breakdown, which is why they may be known as muscle building supplements. Leucine, in particular, is known for playing an important role in muscle protein synthesis, which can help with muscle gain and maintenance. Some also claim that BCAAs can enhance performance, although many studies also refute this claim.

You can't scroll through Instagram without clocking a mammoth cheat day feast, but are real-life bodybuilders consuming such a crazy amount of calories every couple of weeks? Not quite. When he’s dieting for a competition, Terry incorporates ‘re-feed days’ into his schedule. This means he eats the exact same food, but essentially doubles the portion sizes.
As a ingredient that has been tested time and time again and shown to positively affect the building of muscle, GAT has taken the highest-quality compound to create Essentials Creatine. Using HPLC-tested pharmaceutical grade creatine that's tested to be 99.9% pure, Essentials Creatine provides 5 grams in every serving which can increase muscle size, boost strength, and enhance muscle recovery. Keep Reading »
Cornelissen, V. A., Defoor, J. G., Stevens, A., Schepers, D., Hespel, P., Decramer, M., Mortelmans, L., Dobbels, F., Vanhaecke, J., Fagard, R. H., and Vanhees, L. Effect of creatine supplementation as a potential adjuvant therapy to exercise training in cardiac patients: a randomized controlled trial. Clin.Rehabil. 2010;24(11):988-999. View abstract.
Recommended Dose: 3-6 grams before or during exercise. A ratio of two parts leucine to one part each of isoleucine and valine appears to be most beneficial. As Krissy Kendall, PhD, explains in "The Top 7 Supplements to Boost Endurance Performance," BCAAs can be just as effective for endurance athletes like runners, rowers, and cyclists as they can be for lifters and bodybuilders.
You don’t have to, but you can. The typical creatine dose is 5 grams once or twice per day, but it’s sometimes suggested that one should “load” creatine by taking 20 to 25 grams per day for the first week of usage. This is then followed with 3 to 4 weeks of 5 grams per day, then a break for a week or two, then repeat. This may bring about more acute increases in strength and muscle size — creatine will “work” more quickly, in other words — but it’s not necessary.

You're aiming to kick start muscle hypertrophy, the cellular process that spurs growth. Researchers have found that the best way to initiate that process is by performing two or three sets of an exercise for six to 12 repetitions, with about 30 to 60 seconds' rest between sets. You're damaging the muscles with the work — then the protein you've been consuming will help build them back up even bigger.
Despite all the awesomeness of hypertrophy, athletes may be more interested in effects on power. Power is the ability to generate high amounts of force in relatively short periods of time — more power means you can pull more weight in low-rep sets — and independent of the hypertrophy, just five to ten grams of creatine per day appears to improve power output by 12 to 26 percent.
Using too much weight, too soon; always start lower than your expected ability and work your way up that first workout. If your form suffers, you are swinging the weight, or using momentum, this indicates you may be using too much weight. Greater momentum increases the potential for injury and reduces the effectiveness to the muscle group being targeted.