Toning vs. Bulking Up: The Real Facts

The Truth: I'm not sure who first pioneered this idea that heavy weights will bulk you up, but it has stuck over the years and erroneously makes many people—both men and women—afraid of lifting heavy weights. While there is some truth to the idea that lifting lighter weights for more reps does a better job of increasing the muscular endurance, lighter weights will not help you "tone" better than heavy weights. In fact, because heavier weights build the strength of your muscles (and the size to a small degree—no Hulk action here), thereby helping to increase your metabolism and burn fat, lifting heavier weights with fewer reps (8 to 12 on average) and working until you're fatigued is more effective at helping you reach your toning goals than lifting lighter weights. Not to mention that it's more time efficient, too!

The Truth: If you've been avoiding weights because you think that building muscle means that you'll bulk up, think again. When you lift weights that are challenging, you actually create micro-tears in the muscle fibers. These tears are then repaired by the body (this is where soreness comes from!) and in that process the muscle becomes stronger and a little bit bigger. However, because muscle tissue is more dense than fat, adding a little bit more muscle to your body and decreasing your fat actually makes you look leaner—not bigger. To really bulk up, you have to really work with that goal in mind. Bodybuilders spend hours and hours in the gym lifting extremely heavy weights, along with eating a very strict diet that promotes muscle gain. The average person's workout and diet—especially a calorie-controlled diet—doesn’t' result in the same effects.

The Truth: When it comes to lifting weights, the secret to really getting stronger isn't about how much weight you're lifting. Instead, it's all about working your muscle to fatigue where you literally cannot lift the weight for another repetition. The August 2010 study from McMaster University that proved this found that even when subjects lifted lighter weights, they added as much muscle as those lifting heavy weights. However, the time it takes to reach fatigue with light weights is much longer than the time it takes to reach fatigue with heavier weights. So, if you're like most people and extra time is a luxury, it makes more sense to go heavy and then go home!

The Truth: I see this one all the time at the gym. It's pretty common to see women lift 3- to 5-pound dumbbells to do biceps curls while men pick up the 20-pounders to do the same exercise. Although men are genetically stronger than women, they aren't that much stronger. Second, most women tend to stick to the weight machines or basic leg-work that target the rear end and abs (women's "vanity" muscles), while the guys at the gym are more likely to be seen working out with free weights or using barbells and—most often—focusing on their vanity muscles: the biceps and chest.

Obviously gender differences exist and everyone has different goals (like we discussed in the beginning). But if you really want to lose weight and get lean—no matter if you call that toning or bulking—people of both genders should have a strength-training plan in place that works every major muscle in the body at least 8 to 12 times, using a weight that is heavy enough that the last two repetitions are darn hard to lift. Only then is the body challenged enough to change, grow and adapt, making you stronger and leaner no matter if you're male or female. Lifting this way is also a great way to lose weight.

The Truth: Many forms of exercise claim to lengthen the muscles or develop "lean" muscles, not bulky ones. But here's a truth that may be shocking to some: To put it another way, no form of exercise makes muscles "longer" because your muscles do not—and will not—respond to exercise by getting longer. It's just not how they work. Muscles are a certain length because they attach to your bones. A wide variety of movements and exercises can help you strengthen your muscles without necessarily making them bigger. In fact, you can develop a lot of muscular strength without your muscles ever increasing in size (girth).

That said, exercises such as yoga, Pilates, dance and barre classes can help to increase your flexibility (improving your range of motion at certain joints) and your posture, which can give you the illusion of feeling and looking longer or taller. But lengthening? Not possible. Claims like these are just trying to appeal to people who fear bulking up.