Which Comes First, Cardio or Weights

subjects cycle as hard as they can for 30 seconds, then rest for four minutes, and repeat four to six times

into “high-intensity interval training” (HIT)

every additional mile in your average daily run lowers your glaucoma risk by 8 percent. And speeding up your 10K time by one meter per second (the difference between, say, finishing times of 53 minutes and 40 minutes) lowers heart attack risk by about 50 percent.

According to researchers like Paul Williams of the Lawrence Berkeley National Laboratory, you keep piling up more and more benefits. Williams has been following a cohort of 120,000 runners since 1991, tracking how much they run and what happens to their health. With this enormous sample size, his National Runners’ Health Study has been able to uncover a pronounced “dose–response” relationship between aerobic exercise and health: the more you do, and the harder you do it, the more benefits you get.

of Tokyo study published in 2010 saw the biggest increases in strength after two months and the biggest boost in muscle size after three months. To achieve these rapid gains, the subjects were doing four very hard workouts a week. For the average person at the gym, it will take six months or more to see significant sculpting of the body—even though strength has been increasing from day one.
Weight loss is more difficult to predict, because it depends on your starting point, your health history, your genetics, and your diet as well as your workout routine. But like strength training, aerobic exercise produces major health and performance benefits long before you see them in the mirror.

After all, the most effective program is the one you can stick with!