Which Comes First, Cardio or Weights_ - Alex Hutchinson [3]
The bottom line: “Getting in shape” is a journey that extends over months and even years, but the process—and the benefits—start as soon as you begin exercising. So if you’re having trouble staying motivated without immediate physical changes, track your strength and endurance gains along the way.
Am I exercising enough?
This is a hugely controversial question, but not in the way you might expect. Almost all experts agree about what the science says—but they’re bitterly divided about what message they should convey to the public. Decades of research have made two things crystal clear:
1. Every bit of exercise helps, even in scraps as short as 10 minutes.
2. More is almost always better.
The challenge is conveying the second message without discouraging the people who are still struggling with the first. And there are a lot of people struggling: in 2008, the Centers for Disease Control and Prevention found that a quarter of Americans hadn’t done any physical activity at all in the previous month. And less than half met the modest government-mandated Healthy People 2010 goal of 30 minutes of moderate exercise five times a week. In Canada, only a third of people are meeting a similar goal of 30 minutes at a moderate effort, four times a week.
From a public health perspective, the top priority is getting those inactive people to start moving, even a little bit. Going from zero to slightly active offers the biggest possible health boost, according to a recent National Institutes of Health study that followed 250,000 men and women between the ages of 50 and 71. Those who were just slightly active but didn’t manage to meet the exercise guidelines were 30 percent less likely to die than those who were totally inactive. Stepping it up to moderate exercise reduced risk by only eight more percent, and adding in some vigorous exercise subtracted an additional 12 percent. When you combine that data, you find that getting half an hour of moderate to vigorous exercise five times a week cuts your risk of dying from all causes in half. So far, so good. The controversy starts when you ask what happens if you do more exercise than the government guidelines recommend. 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.
What kind of benefits, you ask? Well, in a series of studies stretching back over a decade, Williams has found that the risk of everything from big killers like diabetes, stroke, and heart attack to less common conditions like glaucoma, cataracts, and macular degeneration can be reduced by as much as 70 percent by going beyond the standard exercise guidelines. In every case, the benefits relate to both how much running the subjects do and how fast they do it. For example, 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.
It is true that overdoing your workout regimen can weaken your immune system (later in this chapter), especially if you’re not eating and sleeping well. And elite athletes training for hours a day at extremely high intensities sometime suffer from “overtraining” syndrome. But the message of Williams’s research is that the risks of doing too much—and these