The First 20 Minutes: The Surprising Science That Reveals How We Can Exercise Better, Train Smarter, Live Longer

found that sessions on a flat treadmill required about 5 percent less energy than running outside. To better approximate running over ground, the scientists concluded, you should set your treadmill to a 1 percent grade.

VO2 max = 100.5 – 0.1636 (your body weight in kilograms) – 1.438 (your mile time) – 0.1928 (your resting heart rate) + 8.344 (1 if you’re a man; 0 if you’re a woman). For

man in his 40s who can run an 8-minute mile is in the highest fitness category, according to research from the Cooper Institute.

likely that constant training leads to an overreaction by the body’s immune system. It starts producing too many inflammatory molecules, which communicate with circulating blood cells and cause them to ramp up the production of chemicals that can inflame the whole body

my experience, a large percentage of the people who train for ten-Ks, half marathons, and marathons are overtrained by the time they reach the starting line. Same with cyclists and cross-country skiers. A very high percentage get into a state of fatigue that they just cannot get out of.”

Other studies have found that recreational runners who drop the volume of their training by 30 to 75 percent improve their 5K times by as much as 6 percent.

compelling South African study of bike racers found that those who reduced the intensity of their workouts by 50 percent in the two weeks before a time trial finished more speedily than those who hadn’t tapered

In other words, yoga, based on the limited, current science, represents a fine compromise between inactive and active rest. This is good news, since I had planned to continue attending yoga classes whether scientists approved or not.

to lactate or teaching the lungs how to breathe harder.” It’s also about getting your brain to accept new limits by pushing yourself, safely.

fatigue occurs not simply because muscles get tired, but because the brain tells them they’re tired (even though they almost certainly have some reserve fuel and strength remaining), then you can teach your brain to hold off a bit longer, if you should so desire. “I think the training effect of the theory that fatigue occurs in the mind as well as in the muscles is potentially very profound,” Dr. Tucker says. In that case, training “is no longer simply an act of getting the muscles used