Which Comes First, Cardio or Weights_ - Alex Hutchinson [42]
You have two basic options to make your muscles stand out and look more defined: you can make the muscles bigger, or you can shrink the layer of fat covering them. Reducing fat is a whole-body problem—you can’t just target the fat on your arms (see Chapter 9 for more on reducing weight). Building muscle has long been thought to depend on lifting weights that are at least 40 to 50 percent of your “one-repetition maximum,” the heaviest weight you can lift for that exercise. For advanced resistance trainers, the threshold may be closer to 60 percent. More recent research suggests a simpler rule: whatever weight you use, you should be unable to lift it again when you complete the set. Studies have consistently found that many gym users choose weights that are too low to have any significant effect. For women in particular, avoiding muscle growth is often seen as a good thing. A 2008 study of women working out in New Jersey gyms found that 38 percent of them “believed that the mere act of resistance training would lead to large, ‘bulky’ muscles.” There’s an important discussion to be had about gender stereotypes and healthy body images—but even if we accept the unfortunate premise that muscles are bad, the survey still reflects a highly distorted view of what it takes to build muscle. (Or to put it another way, they should be so lucky!)
CHOOSING THE RIGHT WEIGHT
Strength training guidelines often refer to your “one-rep max,” or “1RM”—the heaviest weight that you can lift once for any given exercise. The American College of Sports Medicine suggests that beginners work with weights that are 60 to 70 percent of 1RM for 8 to 12 repetitions; using less than 50 percent of 1RM may not stimulate any muscle growth.
But how do you determine 1RM? For most people, trying to lift the heaviest weight possible is an unnecessary injury risk. Instead, use trial and error to find a weight that has you reaching “failure” near the end of your final set. If you plan three sets of 10 reps and you successfully complete them, increase the weight slightly next time so that you’re unable to complete the final one or two reps. New research by Stuart Phillips at McMaster University suggests that reaching failure is the most important factor in building muscle—even more important than how heavy the weights are or how many reps you do. His study found that volunteers lifting at 30 percent 1RM synthesized just as much muscle protein as volunteers lifting at 90 percent 1RM, as long as they lifted to failure.
The take-home: don’t worry too much about one-rep max, but choose a weight so that you reach failure, or at least come very close.
Workouts with light weights and a high number of repetitions do have a place in building muscular endurance. Even then, the weight should be heavy enough that you struggle to complete the final set of each exercise, no matter how many repetitions you’re doing. But if it’s “toning” you’re after, your best bet is to choose routines that build muscle size by lifting heavy weights with multiple sets—for example, up to six sets of each exercise, with 6 to 12 repetitions in each set—or else focus on mixing strength, cardio, and diet for overall weight loss.
What’s the difference between strength and power?
A major-league fastball takes a little less than half a second to cross home plate. According to a classic 1967 study, the batter has 0.26 to 0.35 seconds to make up his mind, and then 0.19 to 0.28 seconds to swing. To be a great hitter, it doesn’t matter if you can bench-press triple your body weight if you can’t unleash that strength quickly. Power is defined as “force times velocity,” and it represents the ability to deliver a large amount of strength in a short period of time.