Supplement Zone - Issue 15

Take Citrulline Before Bed

Bodybuilders are notorious for having on-seasons and off-seasons;
often, they may spend more time in a caloric deficit than a surplus. It would be ideal if researchers found a supplement that could help maintain muscle mass when people are on low-calorie diets. French scientists think they’ve found an answer. L-citrulline is an amino acid, so it’s a building block for protein, but it also happens to be a precursor of arginine. Citrulline provides source material for arginine production, which can be used for the production of nitric oxide. NO is essential for what bodybuilders refer to as “the pump,” or, in other terms, vascular function and blood flow. In this study, scientists were using it for its potentially anabolic protein purpose. In the beginning, researchers put female rats on a two-week diet, during which they were given 60 percent of the food they’d eat if they were allowed to eat as much as they wanted (this was to simulate a human’s dieting deficit). When these rats were given a 1-gram dose of L-citrulline before bed, they were able to lose less muscle mass than the group that didn’t receive supplementation. What it came down to was that during a dieting phase, L-citrulline is a muscle growth enhancer and decreases the amount of catabolism

Stack HMB for Fat Loss

Most serious bodybuilders know about the three branched-chain amino acids: leucine, isoleucine, and valine. Of the three, leucine gets the most attention because, along with its metabolite HMB, it’s responsible for stimulating the production of muscle fibres and reducing fat. The reason for its anabolic properties is that it enhances the activity of the enzyme SIRT1, which plays a role in energy metabolism. SIRT1 is involved in the production of mitochondria, which enable cells to burn carbsand fatty acids, thus generating more energy. Resveratrol, which you’ve likely heard of for its antioxidative properties, is also becoming a more well-known supplement in the industry. University of Tennessee researchers wondered whether combining the two supplements would have an additive effect on energy metabolism/ anabolism/fat burning. Researchers gave mice food that had been enriched with nothing, resveratrol, leucine, HMB, or combinations of these. After six weeks, those in the combo group had 35 percent less fat than those in the control group. One of the reasons for the animals’ weight loss, the researchers surmised, was that the animals taking leucine/ HMB and resveratrol had decreased insulin levels and increased uptake of glucose in the muscles. The two supplements boosted the rate of fat burning, as well as the activity of the AMPK enzyme. AMPK is the enzyme responsible for the stimulation of fatty acid oxidation, lipogenesis (converting simple sugars to fatty acids), and stimulation of skeletal muscle fatty acid oxidation and muscle glucose uptake—
all of which contribute to fat loss