Chin-Ups. The chin-up is the easiest way to determine someone’s relative strength. If you can knock out sets of bench with your bodyweight but can’t perform at least 5 bodyweight chin-ups then it’s time to re-evaluate your priorities. Chin-ups are an excellent mass builder for the lats, biceps, and upper back so they should take the place of machine variations like lat pulldowns whenever possible.
I'm 6'1" 175 pounds 27 years old. I would like to increase my general muscle mass and reduce my stomach fat. I would consider myself and ectomorph (hard gainer) as I have never really developed much muscle while I've always been very active in sports and periodic weight training. Over the past year I lost about 30 pounds (nearly all fat) by reducing my caloric intake effectively and regular whole body exercises. I was on my way to my ideal body composition until I became a bike courier. I've been a bike messenger for 9 months and recently my stomach fat has started to return. I'm riding 50+ miles each weekday riding for 9 hours a day. How many calories should I be eating? I've tried everywhere between 2400-3,500 cal/day. Is it possible for me to be eating too few calories while still accumulating stomach fat? Is it realistic for me to be able to maintain or even build muscle mass in this scenario? Please help, thanks.

How to Take It: If you decide you want to take BCAAs as one of your weight lifting supplements, you can easily get them and take them much like you would protein powders. One scoop provides 2.5g of leucine, 1.25g of isoleucine and 1.25g of valine. Take it before a workout, during or after. As with all supplementation, the aim is to reach your overall daily needs and goals.
Testosterone replacement therapy is currently only FDA approved for men who have been diagnosed with hypogonadism, but it’s also prescribed off-label for older men who take it in hopes that it will improve their libido. The use of testosterone therapy is increasingly common in the United States, with more than 2 million men receiving the therapy. Not every man benefits from taking testosterone supplements. Testosterone is available in different forms, including topicals such as gels, creams, and patches; injections; and pellets that are surgically placed directly beneath the skin. (7)

Creatine ingested through supplementation is transported into the cells exclusively by CreaT1. However, there is another creatine transporter Crea T2, which is primarily active and present in the testes [12]. Creatine uptake is regulated by various mechanisms, namely phosphorylation and glycosylation as well as extracellular and intracellular levels of creatine. Crea T1 has shown to be highly sensitive to the extracellular and intracellular levels being specifically activated when total creatine content inside the cell decreases [12]. It has also been observed that in addition to cytosolic creatine, the existence of a mitochondrial isoform of Crea T1 allows creatine to be transported into the mitochondria. Indicating another intra-mitochondrial pool of creatine, which seems to play an essential role in the phosphate-transport system from the mitochondria to the cytosol [13]. Myopathy patients have demonstrated reduced levels of total creatine and phosphocreatine as well as lower levels of CreaT1 protein, which is thought to be a major contributor to these decreased levels [14].

Forbes, S. C., Sletten, N., Durrer, C., Myette-Côté, E , Candow, D., & Little, J. P. (2017, June). Creatine monohydrate supplementation does not augment fitness, performance, or body composition adaptations in response to four weeks of high-intensity interval training in young females. Human Kinetics Journals, 27(3), 285-292. Retrieved from

If you'’re looking to add muscle mass to your frame, hitting the weights hard is a given. Quality time in the gym begins a cascade of changes that will stimulate your muscles to grow bigger in response to the challenges you throw their way. It'’s tempting to think that'’s all it takes to add muscle to your body. After all, you can actually feel your biceps growing after an intense set of curls.

If you'’re looking to add muscle mass to your frame, hitting the weights hard is a given. Quality time in the gym begins a cascade of changes that will stimulate your muscles to grow bigger in response to the challenges you throw their way. It'’s tempting to think that'’s all it takes to add muscle to your body. After all, you can actually feel your biceps growing after an intense set of curls.

The hormone also plays a role in sex drive, sperm production, fat distribution, red cell production, and maintenance of muscle strength and mass, according to the Mayo Clinic. For these reasons, testosterone is associated with overall health and well-being in men. One 2008 study published in the journal Frontiers of Hormone Research even linked testosterone to the prevention of osteoporosis in men.
A child’s ability to regenerate high energy phosphates during high intensity exercise is less than that of an adult. Due to this, creatine supplementation may benefit the rate and use of creatine phosphate and ATP rephosporylation. However, performance in short duration high-intensity exercise can be improved through training therefore supplementation may not be necessary [54].

Creatine kinase enzymes (of which there are numerous isozymes) exist in both the mitochondria and the cytosol of the cell.[45][40] The four isozymes of creatine kinase include the Muscle Creatine Kinase (MCK), present in contractile muscle and cardiac muscle, and the Brain Creatine Kinase (BCK), expressed in neuron and glial cells and several other non-muscle cells. These two creatine kinases are met with Sarcolemmic Mitochondrial Creatine Kinase (sMitCK), expressed alongside MCK, and the ubiquitous Mitochondrial Creatine Kinase (uMitCK), which is expressed alongside BCK everywhere else.[25][39]

It also had a purpose. It turns out posing in powerful stances causes your testosterone to increase within 20 minutes [13,14]. In those two studies, power posing for just a few minutes also dropped cortisol and boosted confidence. It’s a great way to start your day, or to give yourself an edge before a job interview or a big presentation. They don’t call it “warrior pose” for nothing!
Collectively the above investigations indicate that creatine supplementation can be an effective strategy to maintain total creatine pool during a rehabilitation period after injury as well as to attenuate muscle damage induced by a prolonged endurance training session. In addition, it seems that creatine can act as an effective antioxidant agent after more intense resistance training sessions.
In females, the combination of SSRIs (to increase serotonin levels in the synapse between neurons) and creatine shows promise in augmenting the anti-depressive effects of SSRI therapy[230]. Another pilot study conducted on depression and females showed efficacy of creatine supplementation.[231] The one study measuring male subjects noted an increase in mood and minimal anti-depressive effects, but it is not know whether this is due to gender differences or the model studies (post-traumatic stress disorder).[232]

Any type of running will help strengthen your glutes, but sprinting at a very fast speed is even more effective. You can perform sprints as part of a HIIT workout or simply increase your speed while running or briskly walking for a short distance. Start out with about 15–20 minutes of HIIT intervals and work your way up to 25–30 minutes if you’d like.  To perform intervals alternate slower running or resting for 1–2 minutes with 30–90 seconds of sprinting as fast as you can. Most experts recommend practicing HIIT workouts 2–3 times per week.

Bodybuilding supplements are dietary supplements commonly used by those involved in bodybuilding, weightlifting, mixed martial arts, and athletics for the purpose of facilitating an increase in lean body mass. The intent is to increase muscle, increase body weight, improve athletic performance, and for some sports, to simultaneously decrease percent body fat so as to create better muscle definition. Among the most widely used are high protein drinks, branched-chain amino acids (BCAA), glutamine, arginine, essential fatty acids, creatine, HMB,[1] and weight loss products.[2] Supplements are sold either as single ingredient preparations or in the form of "stacks" – proprietary blends of various supplements marketed as offering synergistic advantages. While many bodybuilding supplements are also consumed by the general public the frequency of use will differ when used specifically by bodybuilders. One meta-analysis concluded that for athletes participating in resistance exercise training and consuming protein supplements for an average of 13 weeks, total protein intake up to 1.6 g/kg of body weight per day would result in an increase in strength and fat-free mass, i.e. muscle, but that higher intakes would not further contribute.[3] The muscle mass increase was statistically significant but modest - averaging 0.3 kg for all trials and 1.0–2.0 kg, for protein intake ≥1.6 g/kg/day.[3]
Before supplementation, our intramuscular pools of creatine and phosphocreatine are usually at about 70% of their full capacities. The levels of these pools can be raised by increasing dietary creatine. As vegans and vegetarians omit many creatine-rich foods, they tend to have lower creatine pools than omnivores and hence tend to benefit more from creatine supplementation. At the other end of the spectrum, creatine ingestion doesn’t increase creatine stores in a small proportion of people. It follows that these individuals don’t seem to experience the benefits of creatine supplementation.
Heath suggests incorporating dropsets into your training routine by immediately decreasing the weight and repping out again to failure. “Dropsets overload the muscle with shorter rest periods and increasing volume which you need to grow,” says Heath. “That overload improves your body’s abilities to utilize more nutrients, natural growth hormone, and natural testosterone into those areas and makes the supplements you take more effective.” Heath’s favorite way to do dropsets is on a pin-loaded machine since it’s faster to switch weights.

Intensive weight training causes micro-tears to the muscles being trained; this is generally known as microtrauma. These micro-tears in the muscle contribute to the soreness felt after exercise, called delayed onset muscle soreness (DOMS). It is the repair of these micro-traumas that results in muscle growth. Normally, this soreness becomes most apparent a day or two after a workout. However, as muscles become adapted to the exercises, soreness tends to decrease.[22]

Less muscle breakdown can also help to reduce post-workout muscle soreness levels. During workouts, the body creates lactic acid as it works to generate extra energy. The buildup of lactic acid can cause muscle fatigue, swelling, and tenderness. Improving the ability of the body to recover can help to more effectively clear out lactic acid, reducing inflammation and soreness.

Any type of running will help strengthen your glutes, but sprinting at a very fast speed is even more effective. You can perform sprints as part of a HIIT workout or simply increase your speed while running or briskly walking for a short distance. Start out with about 15–20 minutes of HIIT intervals and work your way up to 25–30 minutes if you’d like.  To perform intervals alternate slower running or resting for 1–2 minutes with 30–90 seconds of sprinting as fast as you can. Most experts recommend practicing HIIT workouts 2–3 times per week.

There is some research that suggests that creatine can help people with type 2 diabetes by improving insulin sensitivity, glucose uptake into the cells, and glycemic control. This has led many people with T2 to start supplementing their diets with pure creatine to try and reap the benefits. At this time there has been no conclusive research done into the effectiveness of creatine for type 1 diabetics.

You've figured out the exercises you should be doing, but what about the number of sets and repetitions? Your decision should be based on your goals. The American College of Sports Medicine recommends 4 to 6 reps for strength and hypertrophy, 8 to 12 reps for muscular strength and 10 to 15 reps for muscular endurance. They also recommend at least one set of each exercise to fatigue although you'll find that most people perform about 2 to 3 sets of each exercise. In general:
2. What's your training like? Are you crushing 25 sets for chest like the average juiced out bodybuilder? If so, there's a pretty good chance you might be working above your MRV (maximal recoverable volume) and as such any physiological adaptation which could have taken place is going to be minimal given the cellular environment which occurs in a state of functional overreaching.
This is another thing I am very tired of hearing. 'No matter what I do or what I eat, I can't gain weight'. I have heard this countless times and I am here to tell you that you are dead wrong. That's OK, because I actually said the same thing until I realized the truth. Most people think they are eating a lot and you just may be. But no matter what you are eating, if you are not gaining, you are not eating enough. Most times, you should re-evaluate your diet as well and focus on more calorie dense foods. But you need to eat more if you are not gaining.

When looking for a whey protein powder to purchase, seek out powders that offer at least 20 g of protein per serving (one scoop) and are low in carbohydrates (aim for 5 g per serving or less). You may run into whey protein isolate, which looks attractive because it’s a higher concentration of protein. However, avoid this one as in the extreme processing, proteins are denatured that can render them less effective. In addition, these formulas are also often chock full of artificial sweeteners. Instead, look for powders from grass-fed cows that aren’t pumped with hormones.

How to do it: Lie flat on your back with your feet firmly planted on the floor, knees bent, as if you’re doing a standard bridge. Keeping one foot fixed to the ground, lift the other up, keeping the bend in your knee. Drive your hips up toward the ceiling, driving through your planted leg and using the raised leg to keep your pelvis even and balanced. Don’t let your non-working leg/side drop, Reames advises, and keep emphasizing the heel plant. Lower toward the ground, then repeat.
Perform the workout three days a week for four weeks, resting at least one day between each session. On the weight exercises, choose a load that allows you to complete a few more reps than the prescribed number (you may need to adjust this load between sets as you discover your strength levels). For instance, if an exercise calls for 12 reps, choose a load that you estimate you can perform 15 reps with before having to stop (but complete only 12).
Over time, we naturally lose muscle mass in a process called sarcopenia. On average, men lose about 30% of their muscle mass during their lives. Usually, this begins in your 30s and progresses slowly as you age. But, don’t despair. You can rebuild and maintain muscle mass even as you age. Often, diet and exercise are enough. But, sometimes, if the above hormones play a role, your doctor may recommend medications and additional treatments (4).
As blood levels of testosterone increase, this feeds back to suppress the production of gonadotrophin-releasing hormone from the hypothalamus which, in turn, suppresses production of luteinising hormone by the pituitary gland. Levels of testosterone begin to fall as a result, so negative feedback decreases and the hypothalamus resumes secretion of gonadotrophin-releasing hormone. 
So, one way to make the soreness go away, at least temporarily, is to continue exercising.  This increases blood flow to the muscles and helps them heal.  However, remember that we still need them to heal. So if you’re sore from heavy squats, don’t turn around and do heavy squats again. Try doing squats with no weight or yoga/stretching to help bring the soreness down.
No. It’s not easy for everyone to get the recommended amount of protein in their diets through good eating habits alone. Others may not have clinically low testosterone, but still benefit from boosting their levels to improve their muscle building capacity. You can fix these common problems through muscle building supplements. These easy to take pills and powders can also help you boost your performance at the gym which will, in turn, spur your body’s muscle building and recovery response.
The first thing you need is a weight training program that signals the muscle building process to begin. Research has shown that a well designed program will generate this “signal” via a combination of progressive tension overload (as in, getting stronger over time), metabolic stress (as in, fatiguing the muscle and getting “the pump”), and muscular damage (as in, actual damage to the muscle tissue itself).
Although creatine is a natural component of food, the amount of food required to supersaturate the muscle with PCr may not be feasible. For example, it could require 22 pounds of meat daily [8]. If creatine monohydrate is proven to be a safe and effective ergogenic aid, creatine supplementation may be the simplest way to increasing muscle stores. It may be beneficial to avoid caffeine if taking creatine supplements. One study showed that caffeine diminished strength gains seen with creatine use [9].
Although weight training is similar to bodybuilding, they have different objectives. Bodybuilders use weight training to develop their muscles for size, shape, and symmetry regardless of any increase in strength for competition in bodybuilding contests; they train to maximize their muscular size and develop extremely low levels of body fat. In contrast, many weight trainers train to improve their strength and anaerobic endurance while not giving special attention to reducing body fat far below normal.

When looking for a whey protein powder to purchase, seek out powders that offer at least 20 g of protein per serving (one scoop) and are low in carbohydrates (aim for 5 g per serving or less). You may run into whey protein isolate, which looks attractive because it’s a higher concentration of protein. However, avoid this one as in the extreme processing, proteins are denatured that can render them less effective. In addition, these formulas are also often chock full of artificial sweeteners. Instead, look for powders from grass-fed cows that aren’t pumped with hormones.
Another double-blind study supplemented with 18.75 g/day of creatine monohydrate for 5 days prior to high-intensity intermittent work to exhaustion, and then 2.25 g/day during testing. The workouts consisted of cycling to exhaustion using several protocols: (a) nonstop, (b) 60 seconds work/120 seconds rest, (c) 20 seconds work/40 seconds rest, and (d) 10 seconds work/20 seconds rest. Creatine supplementation significantly increased the total work time for all four protocols [13].
^ Jump up to: a b c d e Cooper R, Naclerio F, Allgrove J, Jimenez A (July 2012). "Creatine supplementation with specific view to exercise/sports performance: an update". Journal of the International Society of Sports Nutrition. 9 (1): 33. doi:10.1186/1550-2783-9-33. PMC 3407788. PMID 22817979. Creatine is produced endogenously at an amount of about 1 g/d. Synthesis predominately occurs in the liver, kidneys, and to a lesser extent in the pancreas. The remainder of the creatine available to the body is obtained through the diet at about 1 g/d for an omnivorous diet. 95% of the bodies creatine stores are found in the skeletal muscle and the remaining 5% is distributed in the brain, liver, kidney, and testes [1].
Brain injury. Early research shows that taking creatine by mouth daily for 7 days increases the ability to exercise by increasing lung function in people with a spinal cord injury. However, other research shows that creatine does not improve wrist muscle or hand function. Early research also shows that taking creatine by mouth daily for 6 months reduces amnesia following a traumatic brain injury in children.
Simply put, glute activation is waking up your glutes. It makes the connection from your brain to your muscle and gets the muscle fired up and ready to do some work. Glute activation should be done prior to your workout, but it can also be done as an active rest between sets. And trust me when I say that doing some glute activation prior to your squats, lunges, and deadlifts will result in an excellent glute workout!

The winner of the annual IFBB Mr. Olympia contest is generally recognized as the world's top male professional bodybuilder. The winner of the Women's Physique portion of the competition is widely regarded as the world's top female professional bodybuilder. The title is currently held by Juliana Malacarne, who has won every year since 2014. Since 1950, the NABBA Universe Championships have been considered the top amateur bodybuilding contests, with notable winners such as Reg Park, Lee Priest, Steve Reeves, and Arnold Schwarzenegger. Winners generally go on to become professional athletes.
Recommended dose: The fastest way to increase muscle creatine stores is to follow the loading method of 20 grams per day for 5-7 days, followed by the standard maintenance dose of 5 grams per day. However, a lower dose of 5 grams for 28 days will also increase creatine stores without causing the 2-4 pound weight gain typically seen with a loading protocol.
The main consequence to using weight training exercises is the increase in muscle strength that you'll develop over time. You'll also develop stronger bones as well as gain a better general posture. In short, maintaining good muscle strength will allow your body to move more freely from the moment you wake up in the morning to the moment you fall asleep at night.
These effects are secondary to creatine being a source of phosphate groups and acting as an energy reserve. The longer a cell has energy, the longer it can preserve the integrity of the cell membrane by preserving integrity of the Na+/K+-ATPase and Ca2+-ATPase enzymes.[241][235][236] Preserving ATP allows creatine to act via a nongenomic response (not requiring the nuclear DNA to transcribe anything), and appears to work secondary to MAPK and PI3K pathways.[226]

Low testosterone levels can cause mood disturbances, increased body fat, loss of muscle tone, inadequate erections and poor sexual performance, osteoporosis, difficulty with concentration, memory loss and sleep difficulties. Current research suggests that this effect occurs in only a minority (about 2%) of ageing men. However, there is a lot of research currently in progress to find out more about the effects of testosterone in older men and also whether the use of testosterone replacement therapy would have any benefits.
Even human studies can be misinterpreted or manipulated. A few years ago a then-esoteric trace mineral called boron was found to increase testosterone, but only in older women, as it turned out. When boron was tested in young men engaged in weight training, it proved worthless for increasing testosterone. That doesn't mean boron is useless; it helps the body use the minerals calcium and magnesium, and it appears to increase mental alertness.

Foundational supplements are often overlooked for building muscle, because they work behind the scenes. In actuality, foundational supplements are important to take for building muscle, because they assist with overall health and wellness and contribute to the effectiveness of other muscle building supplements.* Some of the top foundational supplements are:
Men who watch a sexually explicit movie have an average increase of 35% in testosterone, peaking at 60–90 minutes after the end of the film, but no increase is seen in men who watch sexually neutral films.[43] Men who watch sexually explicit films also report increased motivation, competitiveness, and decreased exhaustion.[44] A link has also been found between relaxation following sexual arousal and testosterone levels.[45]
These guys are different than traditional deadlifts in that your legs are more or less fixed throughout the lift. Your knees are slightly bent, but this is mostly a “pulling” exercise initiated by the hamstrings and glutes. It likely is more focused on your hamstrings but they need to be strong as well to make you a stronger and more shapely human.
Creatine is a naturally occurring compound found in muscle in large amounts. Creatine monohydrate is the supplement form and combines is a combination of the amino acids arginine, glycine, and methionine. Creatine drives the important creatine phosphate energy pathway, which is important in high-intensity activity such as weightlifting. Creatine can improve body bulk and training performance in high-intensity activities. Be aware that not everyone responds to creatine supplementation and 30 percent of users may not see any improvement. Women may not benefit as much as men. In weight training, increased strength, bulk, and fat loss are reasonably consistent results.
Creatine has been noted to increase the amplitude (0.5-5mM) and frequency (25mM only) of NMDA receptors, although concentrations of 0.5-25mM also reduced signaling intensity. This was credited to creatine causing an increase in ligand binding of glutamate with an EC50 of 67µM and maximal activity at 1mM creatine (158±16% of baseline).[214] Creatine appears to modulate the polyamine binding site of the NMDA receptor, as it is abolished by arcaine and potentiated by spermidine.[215] This binding site is known to modify NMDA receptor affinity.[216][217]

In my late 20’s, I visited an anti-aging doctor who was one of the pioneers of what we now call functional medicine. I got a full hormone test. Shockingly, my testosterone was lower than my mother’s. No wonder I felt crappy and was overweight. My other sex hormones were out of whack too, especially my estrogen levels. They were high because the little testosterone I did make my body converted into estrogen. I went on a mix of topical replacement testosterone cream, plus small doses of pharmaceuticals like clomid and arimidex in order to keep my other sex hormones functioning properly.
Second, strength training has a much greater level of excess post-exercise oxygen consumption than aerobic exercise.  What does this mean?  When you finish a workout, your body needs to do a lot of work to replenish itself in order to bring itself back to a normal state (the way it was before you worked out).  This takes a lot of energy, and some studies have shown that it can boost your metabolism for up to 38 hours after you finish your workout.
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.
The doctor regularly measured my levels to be sure they were within the normal range for a male my age. In other words, I wasn’t taking ‘roids to get big; I was getting control of hormones that were not functioning well. This is how you should look at testosterone therapy – it is a gentle nudge to help you be in normal ranges, not a big push to get you huuu-yge. If you’re like me, you want “normal ranges” of a 27-year-old, not of a 60-year-old. It’s my plan to keep my testosterone where it is now (around 700) no matter what it takes. Right now, the Bulletproof Diet and the other biohacks I’ve written about do that! I’m 43.
According to research from the University of Stirling, for optimal protein growth, weight lifters need to eat 0.25 to 0.30 grams of protein per kilogram body weight per meal. For a 175-pound person, that works out to 20 to 24 grams of protein at every meal. You’ll get that in three to four eggs, a cup of Greek yogurt, or one scoop of protein powder.

The majority of creatine in the human body is in two forms, either the phosphorylated form making up 60% of the stores or in the free form which makes up 40% of the stores. The average 70 kg young male has a creatine pool of around 120-140 g which varies between individuals [10,11] depending on the skeletal muscle fiber type [1] and quantity of muscle mass [11]. The endogenous production and dietary intake matches the rate of creatinine production from the degradation of phosphocreatine and creatine at 2.6% and 1.1%/d respectively. In general, oral creatine supplementation leads to an increase of creatine levels within the body. Creatine can be cleared from the blood by saturation into various organs and cells or by renal filtration [1].
In the modern bodybuilding industry, the term "professional" generally means a bodybuilder who has won qualifying competitions as an amateur and has earned a "pro card" from their respective organization. Professionals earn the right to compete in competitions that include monetary prizes. A pro card also prohibits the athlete from competing in federations other than the one from which they have received the pro card.[12] Depending on the level of success, these bodybuilders may receive monetary compensation from sponsors, much like athletes in other sports.
^ Jump up to: a b c Brioche T, Pagano AF, Py G, Chopard A (April 2016). "Muscle wasting and aging: Experimental models, fatty infiltrations, and prevention". Mol. Aspects Med. 50: 56–87. doi:10.1016/j.mam.2016.04.006. PMID 27106402. In conclusion, HMB treatment clearly appears to be a safe potent strategy against sarcopenia, and more generally against muscle wasting, because HMB improves muscle mass, muscle strength, and physical performance. It seems that HMB is able to act on three of the four major mechanisms involved in muscle deconditioning (protein turnover, apoptosis, and the regenerative process), whereas it is hypothesized to strongly affect the fourth (mitochondrial dynamics and functions). Moreover, HMB is cheap (~30– 50 US dollars per month at 3 g per day) and may prevent osteopenia (Bruckbauer and Zemel, 2013; Tatara, 2009; Tatara et al., 2007, 2008, 2012) and decrease cardiovascular risks (Nissen et al., 2000). For all these reasons, HMB should be routinely used in muscle-wasting conditions especially in aged people. ... 3 g of CaHMB taken three times a day (1 g each time) is the optimal posology, which allows for continual bioavailability of HMB in the body (Wilson et al., 2013).

Testicular diseases which may cause low T include inherited conditions such as undescended testis, Klinefelter’s syndrome, and acquired conditions such as Mump’s orchitis, trauma to the testicles, and damage caused by cancer treatment. Conditions which may affect the regulatory functions of the hypothalamus and pituitary gland include medications such as opioid pain medications and steroids, kidney failure, tumors, tuberculosis, sarcoidosis, HIV/AIDS, obesity, and physical or emotional stress.
Safety. In general health terms, most medical opinion is that up to three cups of coffee a day are not harmful, and may even have some benefits, although some people respond to the stimulant properties with more problems than others. Heart palpitations and restlessness are experienced by some caffeine drinkers. In pregnancy, one or two cups each day are thought to be without harm to the fetus.
Gain mass: One of the most popular reasons for people to take body building supplements is to gain weight and that is why protein powder is much sought after. Protein is the building block of muscles and therefore, bodybuilders use protein powder to help repair muscles, speed recoveries and preserve muscle mass. They usually consume 1 to 2 grams of protein per pound of body weight every day. 
JAK2 (Janus-Activating Kinase 2) is a novel protein that has been shown to suppress the activity of the creatine transporter CrT in vitro. The effects of JAK2 on CrT are not well-understood in vivo, however. Given that growth hormone activates both c-src (increases CrT activity) and JAK2- which has been found to decrease CrT activity, it is plausible that JAK2 may function as a negative-feedback regulator of creatine uptake. Future research is needed to better understand the role of JAK2 on CrT activity in vivo.
While many of the claims are based on scientifically based physiological or biochemical processes, their use in bodybuilding parlance is often heavily colored by bodybuilding lore and industry marketing and as such may deviate considerably from traditional scientific usages of the terms. In addition, ingredients listed have been found at times to be different from the contents. In 2015, Consumer Reports reported unsafe levels of arsenic, cadmium, lead and mercury in several of the protein powders that were tested.[7]
Your basal metabolic rate (BMR)—the calories you burn just to live—is driven by a host of factors, including your sex, genetics, and age, Tim Church, M.D., professor of preventative medicine at Pennington Biomedical Research Center at Louisiana State University, tells SELF. Research published in the medical journal PLOS ONE also shows that the size of your internal organs plays a huge role in why some people burn more calories at rest than others—in fact, the study found that 43 percent of the differences between people’s metabolic rates can be explained by organ size.
^ Mangano, Kelsey M.; Sahni, Shivani; Kiel, Douglas P.; Tucker, Katherine L.; Dufour, Alyssa B.; Hannan, Marian T. (February 8, 2017). "Dietary protein is associated with musculoskeletal health independently of dietary pattern: the Framingham Third Generation Study". The American Journal of Clinical Nutrition. 105 (3): 714–722. doi:10.3945/ajcn.116.136762. PMC 5320406. PMID 28179224 – via