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Effects of Strongman Training on Testosterone Levels

(03-22-2013) Training to increase muscle Strongman trainingmass is usually done in the gym performing well known exercises such as the bench press or squat or equivalent machines. Athletes interested in increasing strength and power such as football, wrestling, rugby and basketball players are said to greatly benefit from Strongman training. Strongman training incorporates compound movements such as pulling and pressing oddly shaped objects such as stones, sleds, keg barrels, tractor tires and trucks. An important factor in training for muscle mass is an increased testosterone production following a training session. To determine if Strongman training is an effective way to increase muscle mass, researchers from New York conducted the following study investigating the effect of Strongman training on testosterone levels.

Squat vs. Leg Press: Effects on Testosterone, Growth Hormone and Cortisol

(Originally posted on 22-04-2014) WhetherSquat vs leg press training with free weights is more effective than training on machines has been an ongoing debate and both methods have their advantages and disadvantages. To see which has the largest effects on our hormones scientists of the University of North Texas started a study on the effects of two of the most popular leg exercises: the squat vs leg press.

Effects of Amino Acid Supplementation and Resistance Exercise on Muscle Adaptation

Abstract

The purpose of this article is to investigate and evaluate the effects of amino acid supplementation in combination with resistance exercise on muscle hypertrophy and strength. The mechanisms of different processes in protein turnover on which amino acid supplementation has an effect are explored. Amino acid supplementation in combination with resistance exercise increases serum IGF-1 concentrations, decreases testosterone concentrations and leaves myostatin expression unchanged. These processes increase mRNA translation, which results in an increase in hypertrophy and, if resistance training intensity is high enough, in increases in strength. In the end it seems that although not all effects of amino acid supplementation are positive for protein synthesis, the net effect is an increase in protein synthesis.

How to increase muscle mass effectively

One of the most important reasons for many men to train is to increase their muscle mass and look more athletic. To achieve this goal many different training methods have been tried and much research has been done to determine what works and what is less effective or even counter productive. This article will give you best tips science can give you on how to increase muscle mass effectively.

Rest Between Sets during Strength Training

The amount of rest between sets during resistance training is very important because it has a very large impact on the results of your training. When shorter rest periods are used, the training will result in adaptations directed at improving muscle endurance, whereas longer rest periods allow for higher training loads and therefore effective improvement of muscle strength and 1RM.

Local muscle endurance can be very important for athletes who participate in martial arts, and strength training is necessary to improve performance during power lifting events. The amount of rest is essentially determined by the goal of the training. The most used rest periods are between 30-90 seconds, and are a compromise between training for muscle endurance, strength and hypertrophy.

Longer rest periods, from 1,5 minute to 5 minutes allow higher training loads which increases strength. When very short rest periods are used, sometimes shorter than 10 seconds, muscular endurance improves and more growth hormone is produced.

Strength training makes women large and bulky

Fact or fable: Strength training makes women large and bulky

Strength training is often seen as a training form best suited for men
Strength training for women
that want to increase their muscle mass. Women often want to lose weight and certainly don’t want to look like bodybuilders. But does strength training make women large and bulky?

It is true that strength training also increases muscle mass in women, which can cause an increase in total body weight. However this increase will be rather small, because women produce far less muscle mass increasing hormones than men. Only when women have exceptional genetic potential to build muscle mass and perform large volume high intensity strength training will have large increases in muscle mass.

Women who want to lose weight would do well to regularly perform strength training, despite a possible increase in body weight. Strength training stimulates fat metabolism after training and an increase in muscle mass increases resting metabolism. An increased resting metabolism makes it easier to lose weight because even in rest the body needs more energy than before. Moreover, strength training exercises all muscle groups, which causes all muscles to remain firm and give the body a more athletic look.

Other effects of strength training that can be very important for women:

-Increase in bone density: Bones get stronger through strength training. Especially after the menopause bone density can decrease significantly. Strength training can prevent this to a large extent.

-Rejuvenation of body cells: Strength training stimulates the production of hormones in the body that aid the body’s cells with maintenance and recovery. This causes the cells to function better and age less quickly.

For women it is highly recommended to regularly perform strength training. It has many health benefits, but helps in weight loss and improving body composition as well. The fear of looking like a body builder is not necessary. Women don’t have the necessary hormone production to produce and maintain large amounts of muscle mass. Female bodybuilders do this by using anabolic steroids and other substances that stimulate muscle mass.

Split training or full body workout?

What is Most Effective for Muscle Growth: Split Training or Full Body Workout?

Increasing muscle mass and strength are important training goals for many people. Muscle hypertrophyNot only for cosmetic reasons but for health reasons as well, people seek to increase their muscle mass. A much used method to increase muscle mass more effectively, a process also known as hypertrophy, is using a split training program. In a split training program only a few muscle groups are trained every workout. This allows more exercises per muscle group which increases the training stimulus to the muscle compared with performing just one exercise per muscle group.

Unfortunately there has been little research comparing split training with a comparable full body workout up until now. However the following advantages and disadvantages are theoretically supported.

Advantages Split Training in comparison with Full Body Workout

-A stronger and more complete training stimulus per muscle group. As a result of combining multiple exercises in one training session, a larger part of the muscle is targeted which results in a larger number of muscle fibers that need to adapt.

-It allows for a higher training frequency. When the increase in muscle mass from a Full Body workout performed 3 times a week is not sufficient, it is a bad idea to perform this workout 4 times a week or more. This will not allow the muscle to recuperate and increase its’ size. A split training regimen, if designed properly, even allows daily training. While muscle groups that have been trained in a previous workout are allowed to recover.

Disadvantages compared in comparison with Full Body Workout

-It is less suitable for beginners. The training intensity is often too high for relatively untrained muscles. Moreover, most beginners will have a hard time reaching the necessary training intensity at all, since they still have to learn to activate their muscles to a larger extent. When they can’t reach the necessary training intensity, split training often offers few advantages.

-It requires a higher training frequency to train all muscle groups regularly. Ideally muscles are trained when they are fully recuperated and adapted to the previous training stimulus. For optimal results it is recommended to train every muscle group two times a week. When a split training is performed two times a week, the muscle will have recovered by the time it is trained again, but the training adaptations will probably have disappeared as well.

-Smaller increases in growth hormone and testosterone production. The increase in hormone production is strongly dependent on the amount of muscle mass that is active during training. Since split training targets a few muscle groups each training, the hormonal response on training is smaller. Recent studies have shown that this hormonal response is not a requirement of muscle growth. However, it is likely that growth hormone production has other beneficial effects, such as stimulating fat metabolism. A full body workout is probably more effective in this aspect.

Conclusion:

Using a split training regimen has both advantages and disadvantages. Moreover, no studies comparing both split training and full body workouts have been performed. However a split training allows for a higher training frequency and a more complete workout for each muscle group, while other muscle groups are allowed to recover.

References:

-Kraemer, W.J., Ratamess, N.A. Fundamentals of Resistance Training: Progression and Exercise Prescription. Medicine & Science in Sports & Exercise 2004, 36, 4, 674-688.

-Wescott, W.L. How Often Should Clients Perform Strength Training? ACSM’s Certified News 2010, 20, 2, 10-11.

How does strength training increase muscle mass?

The increase in muscle mass due to resistance exercise is a result of several hormone mechanisms. High intensity resistance training increases hormone concentrations of testosterone, growth hormone and IGF-1. These hormones stimulate protein synthesis and therefore increase muscle mass.

Men naturally produce more testosterone and growth hormone and these levels rise more strongly than in women as a result of resistance exercise. In men testosterone seems to be the most important regulator hypertrophy in muscle mass, in women, who produce much less testosterone, this role is reserved for growth hormone.

The amount of these hormones produced depends on several factors, the amount of muscle mass active during training, training intensity and rest periods between series. When more muscles are activated during training, anabolic hormone levels rise. The same applies to higher training intensity and shorter rest durations.

References:

-Heyward, V.H. (2010). Designing Resistance Training Programs. Advanced Fitness Assessment and Exercise Prescription Sixth Edition. USA. Human Kinetics

Testosterone

Testosterone is an androgen (male sex hormone) that promotes the development of secondary male characteristics during puberty.  These include characteristics as a deeper voice, facial hair and an increase in muscle mass. Testosterone stimulates, directly (through testosterone receptors on muscle fibers), and indirectly, (through stimulating Growth Hormone production in the pituitary), hypertrophy. The increase in muscle mass caused by testosterone increases muscle strength. However this is not the only reason muscle strength increases. Testosterone can also bind with receptors on neurons (nerve cells), where it influences the production of neurotransmitter and the structure of nerve cells. Testosterone increases strength not only by increasing muscle mass but by improving muscle activation as well.

Testosterone is primarily produced in the testicles in men, and in the ovaries and adrenal glands in women. Men produce 15-20 times more testosterone than women, and the effect of different training protocols is greater on testosterone levels in men as well. In women, testosterone levels are hardly influenced by strength training or other forms of exercise, which partly explains the lower potential in women for increasing muscle mass.

In addition, an artificial form of testosterone (androgenic anabolic steroids) is used to stimulate muscle strength, hypertrophy and contraction speed, to increase performance in sports and athletic events. Most athletic organizations have banned the use of androgenic anabolic steroids and athletes who are caught using them risk suspension. Moreover, the use of androgenic anabolic steroids increases risk of developing cardiovascular disease and several forms of cancer.

References:

– Baechle, T.R., Earle, W.R. (2008). Endocrine Responses to Resistance Exercise. Essentials of Strength Training and Conditioning. Third Edition. USA. Human Kinetics. -Wilmore, J.H., Costill, D.L., Kenney, W.L. (2008). Ergogenic Aids and Sport. Physiology of Sport and Exercise Fourth Edition. USA Human Kinetics.

Myostatin

Myostatin

myostatin deficient dog

Wendy the myostatin deficient dog

is a cytokine which functions as an antagonist for Insulin-like Growth Factor-1. It is therefore a negative regulator of muscle growth. In other words, it causes the breakdown of muscle tissue. It is an essential substance in maintaining balance in protein synthesis and protein breakdown. This is most obvious in animals that have mutations in their DNA, rendering the myostatin gene less active or even completely shutting it down. These animals have an highly increased muscle mass and look like bodybuilders among their species. This reduces muscle function as well, since myostatin also serves to improve muscle quality. However it also plays a major role in diseases such as muscle dystrophy, where myostatin activity is increased and muscle mass decreases progressively.

Insulin

Insulin is an anabolic hormone which is responsible for transporting excess glucose from the blood into the cells. In healthy person’s blood glucose will rise after a meal rich in carbohydrates. When the blood glucose is high enough, insulin will be secreted from the pancreas’ beta-cells which will transport the glucose to other storage sites, such as the glycogen stores in the muscles or liver, or when those are filled, the fat cells in adipose tissue. It stimulates protein transport into body cells and therefore stimulates muscle hypertrophy. And in addition insulin inhibits the usage of fatty acids to generate energy as well, so the body temporarily depends more on glucose metabolism.

Growth Hormone

Growth hormone is produced in the anterior pituitary gland. The best known function of growth hormone is stimulating cell growth in almost all tissues, hence the name. Growth in children is regulated by growth hormone. In adults it still has many important functions, not the least of which are inducing muscle growth or hypertrophy, stimulating bone mineralization and increasing lipolysis or fat metabolism.

Cortisol

Cortisol, also known as a stress-hormone, is a hormone produced by the adrenal cortex and plays an important role in glucose regulation. Since nerve cells can only produce their energy from carbohydrates and glycogen, when blood sugar levels and glycogen stores are low, cortisol stimulates conversion of protein to carbohydrates. This results in increased protein breakdown and it inhibits protein synthesis, effectively breaking down muscle tissue to produce carbohydrates. Cortisol is secreted during times of stress but high intensity resistance exercise stimulates cortisol production as well. Since resistance exercise also stimulates testosterone and growth hormone production, this is not a negative effect, since these more than counter the influence on hypertrophy of cortisol. In fact, it is believed that cortisol plays an essential role in remodeling muscle tissue after training.