These are just body measurements. In this study, they looked at the basics like body mass, height, and the skinfold test. Some common others include:

• Waist-to-hip ratio
• Limb length/circumference
• BMI

Power is defined as the amount of work done in a given time period, i.e. W/T. From this, there are two ways to increase power if all else is the same:

• Increase the work you do within a given time frame.
• Decrease the time it takes to do a given amount of work.

Another way to think of Power is in terms of Force x Velocity. When you think of “power” with respect to weight lifting, obviously you think of powerlifters. However, the powerlifter title is a bit of a misnomer. These folks usually display maximum strength, but rarely maximum power. This is because of the time component of power. A better example of those “powerlifters” would be Olympic weightlifters, who perform lifts like the snatch, which require a certain speed to complete.

In truth, peak muscular power is usually reached with very light loads, around 30% of a one-repetition max. Still, heavy strength training will have an effect on power as well.

Strength is defined simply as the maximum amount of force that a specific muscle group can produce during one short, discrete period of time, say, for one repetition.

Muscular strength is proportional to the cross-sectional area of the muscle. In other words, the bigger the muscle, the more force it can produce. For the most part, a muscle will not get stronger unless it has gotten bigger.

The exception to this rule is improvement in motor unit recruitment. Essentially, this just means improving the brain-to-muscle connection, which will increase your capacity to produce force without actually increasing the cross-sectional area of your muscles.

The kettlebell has been around in some form or fashion for hundreds, if not thousands, of years. They came to America by way of Russia, where they were first used to measure grains and other goods. Some say that farmers would swing this weight around in a display of strength, as to intimidate anyone who might of thought to rob them.

Either way, it became a Russian folk activity in the late 1700s, and a hundred years later, Dr. Vladislav Kraevsky traveled around Russia to learn more about these odd pieces of equipment. In 1885, he established one of the first weightlifting halls in Russia.

Since then, kettlebells have remained a symbol of health and vitality in Russia. However, once Americans became obsessed with barbells in the early 1900s, kettlebells became rare in the U.S. It wasn’t until 1998 when the “king of kettlebells” himself, Pavel Tsatouline, wrote an article in a popular American magazine, that kettlebells started making a comeback.

There’s been no shortage of fitness product fads appearing on the market over the last decade, but exercise physiologists have consistently reached the same conclusion every time: the most efficient way to load the body with weight is with a barbell.

The first recorded use of the term “barbell” appeared in 1870 at the latest, but barbell’s had been around for much longer, and where first seen in print – under a different name – by 1854 (see: A History of Barbells, Dumbbells, and Indian Clubs). The use of barbells really gained steam around the early 1900’s, when Milo Bar-Bell Co. was established by Alan Calvert. They began selling some of the first plate-loading barbells.

[Eugene] Sandow Inspired Weight Lifting in America…Alan Calvert delivered it!

By the 1920’s, weightlifting was a regular event at the Olympics. It wouldn’t be until the ‘40’s and '50’s that most of the classic power lifts would really become popular, though.

http://youtu.be/B9moGJHmJyg?t=4m6s

As per the annotation on GAS, resistance training produces a “fight-or-flight” response from the body, of which, the release of cortisol plays a major part. Though proteins from the muscle are already being torn apart because of tension being placed on the muscle during resistance training, cortisol actually makes this protein breakdown (catabolism) worse, by stimulating gluconeogenesis – the production of glucose from non-carbohydrate sources, i.e. your muscles actually start to eat themselves..kinda. This is all good and natural, but it becomes a problem the longer that catabolism continues after training.

Brief overview of catabolism/anabolism:
http://youtu.be/ST1UWnenOo0?t=2m21s

Theoretically, the sooner one goes from a catabolic state (muscle breaking down) to an anabolic state (muscle rebuilding), the more absolute muscle they will gain.

The trick is finding out what conditions elicit the best results. Contrary to popular thought, recent research shows that low weight, high rep training might actually stimulate more protein synthesis, but nothing is even close to being confirmed in that arena.

Either way, since PKB/Akt stops the breakdown and starts the rebuild, you see that is extremely important when it comes to gaining muscle.

First, it’s important to understand that resistance training does not build muscle, it breaks down the structural integrity of your muscles…it’s the rebuilding where the magic happens. Essentially, markers of protein synthesis are considered to signify that the body is rebuilding itself.

Anyway, here’s a cool video on the general process of protein synthesis:
http://youtu.be/5iS4CRPPDus

STK’s are a specific group of kinase proteins, which act as enzymes to facilitate certain reactions. STK’s are one of the most common kinases in the human body.

In short, STK’s help regulate cell proliferation. For example, something usually goes bad with the STK’s when someone has cancer. Considering the fact that gaining strength amounts to gaining more muscle cells, it would seem likely that STK plays a big part in strength development.

Increases in physiological functioning, i.e. strength, endurance, etc., are based on Hans Selye’s model of General Adaptation Syndrome. In other words, a powerlifter will get stronger only insofar as they continue to lift progressively heavier weights. These adaptations can occur either through structural changes or efficiency (bioenergetics).

Think about this: those who trained strength and endurance were doing the exact same amount of strength training as the strength-only group, yet their muscles didn’t adapt to the same extent. Physiologists were baffled by this, and it was a long time (20+ years..) before they had the technology to really look into it.