How to Get Stronger, Faster, Fitter, and Healthier as You Age
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How to Get Stronger, Faster, Fitter, and Healthier in Your 40s
Your maintenance-free years are over, says Dr. Harry Fisch, a urologist at New York's Weill Cornell Medical College. Wrinkles deepen, muscles sag, and you pee more frequently. Your testosterone is at least 10 percent lower than it was in your twenties, and you produce, on average, about 30 percent less human-growth hormone, responsible for stimulating cell growth. These hormonal changes cause you to lose muscle mass at a rate of about one percent a year after age 45. Since muscle burns more calories than fat, less muscle mass also means fewer caloric needs, so that by the time you reach 45, you need 200 fewer calories per day than you did in your twenties. Most of us don't adjust our eating accordingly and replace fading muscle with fat. To stop muscle loss and prevent weight gain, tweak your cardio to include interval training – short bursts of high-intensity effort alternated with periods of rest – which can burn calories and increase lean muscle mass more than sustained exercise.

Endurance exercise, like running, cycling, and swimming, can restore your heart's strength and blood pressure to what it was in your twenties, effectively reversing 100 percent of age-related decline in aerobic power. Yet not all endurance training is created equal. A recent study indicates that interval training increases fitness, lean muscle mass, and weight loss. But since you can't bounce back as quickly from exercise as you did in your twenties or thirties, prioritize good recovery habits: Eat after exercise, sleep at least seven hours, drink plenty of water, and space out interval days with easy recovery days.

Ignoring proper recovery can speed muscle loss. Medical Heart disease is the leading killer of men in their forties. Don't waste time with a basic cholesterol screen, but ask for a Vertical Auto Profile (VAP) – an advanced screening that measures 22 markers of heart disease and provides more clues to heart health (it doesn't cost more and most insurance policies cover it). Also, ask for a comprehensive metabolic panel, which can show early warning signs of kidney and liver problems. And it's time for a prostate exam. Opt for a manual rather than a PSA test, which research shows provides little diagnostic value.

Vitamin D Experts advise older men to take 2,000 IUs of vitamin D daily, since studies suggest low levels contribute to cardiovascular ­disease.

You're losing muscle, so it's more important than ever to have good exercise nutrition. Eat a balanced meal with lean protein and whole grains two to three hours before you exercise. If you work out in the morning, wake up early to eat something light like a banana an hour before. Don't snack while you train – you don't need extra calories – and always eat or drink something with protein and carbs immediately afterward, like chocolate milk or a fruit smoothie with protein powder. Also, prioritize eating protein at meals. "As you lose testosterone, it's important to boost your protein to keep lean muscle mass up," says Teitelbaum.

Forty-seven percent of baby boomers are stressed – and that's reason to worry, experts say, since 90 percent of all disease is caused or complicated by stress. One of the most effective ways to reduce stress is deep breathing, which helps block stress hormones. Try counting breaths: Sit with good posture, close your eyes, and try to count 10 complete breaths. If you lose count – which is normal – start over again.

Interval Routine
At least once a week, after a short warm-up, dedicate a portion of your workout to Tabata Intervals – 20-second bursts at 100 percent effort, followed by 10 seconds of complete rest. Do them on the treadmill, track, road, stationary bike, or rowing machine. Repeat the cycle eight times. As your fitness increases, take a two-minute rest after eight intervals before doing another eight.