Ten More Fascinating Body Facts

From the age of thirty, humans gradually begin to shrink in size.
Most people lose fifty per cent of their taste buds by the time they reach age sixty.
Your body contains enough iron to make a spike strong enough to hold your weight.
The amount of carbon in the human body is enough to fill about 9,000 'lead' pencils.
One square inch of human skin contains 625 sweat glands.
The surface area of a human lung is equal to that of a tennis court.
Give a tennis ball a hard squeeze and you use about the same amount of force your heart uses to pump blood around your body.
When you blush, your stomach lining also reddens.
The human body has less muscles in it than a caterpillar.
Your eyes blink enough times in a lifetime to see blackness for over a year.

Relieve Eye Strain

Near-point stress can be caused by staring at your computer screen for too long. Here is a simple solution that is cost free. Every few hours close your eyes, tense your body, take a deep breath, and, after a few seconds, release your breath and muscles at the same time. Tightening and releasing muscles such as the biceps and glutes can trick involuntary muscles, like the eyes into relaxing as well.

Muscles and Fat

Muscles and fats are made up of very different types of cells that have completely different functions.  Skeletal muscles get larger when a person exercises. The muscles get larger, with more filaments being developed within the cells to accommodate the more challenging demand on them.

After a person quits exercising, the muscle cells do not magically turn into fat cells. They just shrink.  This allows the body to conserve energy when a person’s daily activities don’t require as much muscle mass.

The myth that muscles turn to fat when a person stops exercising probably stems from the fact that people who body build or otherwise exercise regularly and quit, tend to put on weight.

It all comes down to caloric intake. People who exercise regularly tend eat more food and when they stop exercising their body loses the need for the calories. These people may not reduce their food intake quickly enough to compensate for their reduced caloric needs.

Burning Calories

On average, 42% of an adult man’s body mass is made up of skeletal muscle.  For women, that number drops to 36% on average. Contrary to popular myth, skeletal muscles consume about 6 calories per pound per day, not 50.  So, if you weigh approximately 180 pounds and are a man, your skeletal muscles will burn around 454 calories per day when you just sit around all day.

Fat cells will burn about 2 calories per pound per day.  How much of your body mass is made up of fat cells varies greatly from person to person, but you can use a body fat test to get that number and then calculate how many calories your fat cells burn per day. Average male is 18% - 25%, female is 25% - 31%. Wow, another 64 burned calories for sitting around.

Bone cells burn about 1 calorie per pound.  If you are a man, on average about 15% of your body mass is made up of bone (another 27 calories for just sitting around).  For women, that number is around 12%. Sit back, relax, burn some calories.

How Much Weight Can You Lift

In the heaviest dead lift recorded, British weightlifter Andy Bolton lifted 457.5 kilograms (1,008 pounds) from the floor to his thigh.

What is the maximum weight a human could ever lift? Todd Schroeder at the University of Southern California in Los Angeles thinks we are already close to the maximum. "If you look over time at the records for maximal lifts, they have crept up but are starting to plateau," he says. "Today's weightlifters, including those that use steroids, are near the limit of human potential."

It is the muscles that set the limit. When something does give way, it is usually the muscle fibers that tear, often near the tendon. It is control of the muscles that gives weightlifters their advantage. The body has natural inhibitory mechanisms designed to keep us from hurting ourselves by trying to lift too much. These work by controlling how many muscle fibers are activated at any one time. Weightlifters learn to suppress these signals, enabling them to use a larger fraction of the muscle's potential in lifting.

The key to success is training and genetics plays a role. Short limbs favor strength and some people have more muscle fibers than others.