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Supported Single-Arm Dumbbell Row

Supported Single-Arm Dumbbell Row

Hold a dumbbell in your right hand, place your left hand on a bench in front of you, and assume a staggered stance, left foot forward. Hold your elbow in as you row the wight to the side of your torso. Do 10 reps, switch arms and leg positions, and repeat the movement.

Dumbbell Triceps Kickback

Dumbbell Triceps Kickback

Grab a pair of dumbbells, bend your knees and lean forward so your torso is nearly parallel to the floor. Tuck your upper arms next to your sides, bend your elbows, and hold your forearms about parallel to the floor, palms facing up. Simultaneously extend your arms straight back and rotate the weight so your palms end up facing each other. Return to the starting position. Do 15 reps.

Dumbbell Hammer Curl and Press

Dumbbell Hammer Curl and Press

Standing with your feet shoulder-width apart, hold a pair of dumbbells at arm's length by your sides, palms facing each other. Without moving your upper arms, curl the weights to your shoulders, and then press them overhead until your arms are straight. Reverse the move to return to the starting position. Do 10 reps.

Tuesday, November 27, 2012

The Benefits of Winter Swimming

To those unaccustomed to it, swimming in icy waters can be life threatening. In some cases exposure to cold water causes a type of thickening of the blood that leads to blood clots in the coronary arteries. In common terms, that causes a heart attack. In other cases the heart rhythm is disturbed, sometimes fatally.

From a hormonal point of view, levels of norepinephrine, a catecholamine hormone known to stimulate the heart, increases fourfold, resulting in non-shivering thermogenesis. Other hormones, including ACTH from the pituitary, which controls cortisol release; thyroid-stimulating hormone (TSH); and cortisol, all rise during exposure to cold water. If exposure exceeds 30 minutes, core body temperatures can decrease enough to cause death.
Ice Swimming

That all changes when people swim in cold water regularly. Just as muscles get accustomed to regular exercise, so too does the body to regular cold-water exposure. The body's thermogenesis reactions upgrade, while the circulatory system adapts to cold, preventing the dangerous effects that would ordinarily occur. The metabolic adaptation prevents a dramatic drop in body core temperature that could lead to cardiovascular collapse.

Regular cold-water swimmers show increased beta-adrenergic stimulation of skeletal muscle that doesn't result from increased catecholamine release. Normally, exercise increases the release of catecholamines such as epinephrine and nore-pinephrine, which interact with beta-adrenergic fat cell receptors to promote fat release. The same event occurs during cold-water swimming minus the presence of catecholamines. Scientists think that the exposure to cold water may increase beta-adrenergic receptor sensitivity.

That has implications for fat-burning during regular exercise on dry land. The sensitivity of beta-adrenergic receptors determines how efficiently you burn fat during exercise. Theoretically, if cold-water swimming increases this sensitivity, you may tap into fat stores easier during standard exercise sessions. Cold-water swimmers also show skin adaptations. They get less blood flow to their skin, which acts as a thermal insulation. That results from the lower heart rate that occurs after regular cold-water exposure. The question is whether any real health benefits are associated with icy swims.

One study found a whopping 50 percent reduction in insulin levels at the end of 2 1/2 months of winter swimming compared to baseline, or starting, levels. Lowering insulin provides a number of beneficial health effects, including decreased risk of diabetes and cardiovascular disease. Excess insulin is also linked to increased bodyfat and decreased longevity.

Other studies show that cold-water swimming galvanizes immune system response. Although it does raise cortisol levels, which are linked to immune-system suppression, it compensates by promoting the release of cytokines, chemi¬cals that prime and promote immune responses in the body. One study showed that regular winter swimmers had a 40 percent decrease in the incidence of respiratory-tract infections. Cold-water swimming may also increase the body's antioxidant protection. Apparently, regular cold-water exposure acts as an oxidant stressor, causing the body to upgrade its an-tioxidant defense system.


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Ultimate 30's Workout

Increase the amount of testosterone and growth hormone your body produces by working multiple muscle groups and keeping rest periods short. For cardio, your lactate threshold can still be increased throughout your thirties, so intervals are king to counter any loss of lung power.


Ultimate 40's Workout

Short, sharp shocks are the way to fire up your body in your middle years - which means you can forget long-winded weights workouts. Vary exercises, intensity and timings to keep your muscles guessing.



Ultimate 50's Workout

You may not be able to lift the heaviest weight, but that's okay. Instead, stretching and yoga should be part of your training, and body-weight moves can replace heavy workouts. Do three sets of 10 reps of the following exercises to protect your joints and maintain muscle mass and testosterone.