Yet despite their contrasting appearances, these two women have very similar body compositions -- probably in the range of 10 to 14 percent body fat.
Elite athletes across all sports are usually very lean. Whether tall or short, broad or narrow, brawny or lithe, they tend to be made of mostly muscle and little fat. This is because muscle is the only tissue capable of performing work, whereas body fat is (from an athletic perspective) merely dead weight.
Few elite athletes spend much time worrying about their body composition. For them, the ideal body composition is simply a byproduct of world-class training and proper diet acting on a one-in-a-million genetic makeup.
On the other hand, most of us mere-mortal athletes have a less-than-ideal body composition and would benefit from improving it. And improve it we can. Although you might not have the genetic potential to become as lean as Ali or Bowden (without compromising your health), you can achieve your own personal optimal body composition by modifying your training and diet appropriately.
It's not a weight game
Optimizing body composition is different from simply gaining or losing weight. Many athletes feel they would perform better (and look better) if they lost weight. But if muscle is lost instead of fat, performance and health will suffer. And the method athletes most often use to lose weight -- general calorie restriction -- is sure to result in muscle loss.
The first step toward optimal body composition is to establish a starting point. Measuring your body fat allows you to pursue the goal of improving it objectively. Three testing methods are relatively inexpensive and convenient. One option is to have a nutritionist or personal trainer estimate your body fat percentage using a caliper to take skin-fold measurements. This will cost you about $25 per test.
A second option is to purchase a body fat tester such as an Omron hand-held body fat tester or Tanita body fat scale for home use. These types of devices use bioelectrical impedance to estimate body fat with reasonable accuracy. You can expect to pay about $50 for one of these devices, which are available through many exercise equipment retailers.
The third option is to use an online body fat calculator to measure your body fat percentage. This may not be as accurate as the first two options but will give you a good sense of your body fat index at zero cost.
Once you've determined your current body composition, set incremental goals to improve it. If you are currently above the acceptable range, set a modest initial goal of losing fat to move into this range. If you're currently in the acceptable range, set a goal of moving into the fitness range. And so on.
The next step is to make a few key changes in your exercise habits and diet. The following five tips are intended for women who are already active and maintain a balanced overall diet:
1. Strength train. By gaining lean muscle mass you can lower your body fat percentage without actually losing body fat. But gaining muscle also helps you burn body fat by raising your resting metabolic rate. In order to gain lean muscle, you need to engage in regular strength training. This is something every athlete should do.
Even endurance athletes such as long-distance runners can benefit from strength training. For example, in a recent Swedish study, trained runners replaced 32 percent of their running with plyometrics. After nine weeks, their maximum sprint speed, running economy and 5k race times improved.
Many female athletes are reluctant to strength train because they fear they will gain weight. But research shows this won't happen if you also get regular cardiovascular exercise.
2. Fuel your workouts and recovery properly. In the new book Nutrient Timing, John Ivy, Ph.D., and Robert Portman, Ph.D., contend that when we eat is as important as what we eat when it comes to optimizing body composition. Specifically, by consuming calories when they are most needed to provide energy and build muscle, we can improve body composition without restricting calories.
At no time can calories be put to better use than before, during and immediately following workouts. Research cited in Nutrient Timing suggests that athletes who consume the right nutrients at these times will improve their body composition more than athletes who take in the same number of calories during the day but at other times.
The pre-exercise meal should be eaten about three hours before exercise and should contain plenty of low- to moderate-glycemic carbohydrates (such as whole grains) to provide energy for the workout. During exercise, use a sports drink to prevent dehydration and increase endurance.
After exercise, try to consume 10 to 20 percent of your daily carbohydrate and protein intake within 45 minutes. By doing so you will maximize muscle glycogen storage and muscle protein building. If you consume the very same meal two hours later, much more of it will be stored as fat.
3. Frontload your daily food intake. Another way to use the nutrient-timing principle is to eat more of your calories earlier in the day, when you're most active. Eat a good-size breakfast and lunch, a modest-size dinner, and limit snacking in the evening when you're likely to be most sedentary.
A study performed at the University of Massachusetts found that those who regularly skip breakfast are 4.5 times more likely to be overweight than those who eat it!
4. Increase your cardiovascular fitness. Nothing gets rid of body fat like cardiovascular exercise. Cardiovascular fitness is also essential for optimal performance in all sports. By modifying your training to increase your cardiovascular fitness for the sake of performance, you can also lower your body fat.
The three ways to enhance your cardiovascular fitness are to increase the frequency, duration and intensity of cardiovascular workouts. But don't make the mistake of increasing them all at once -- you'll only be setting yourself up for injury and/or overtraining. The best approach is to manipulate each of these variables to gradually and steadily improve your fitness (and body composition) until you reach a peak for your most important competition.
Small changes go a long way. Adding just one cardiovascular workout to your weekly schedule, or increasing the intensity or duration of just one weekly workout, can offer a significant boost.
5. Eat enough protein. Protein is the main structural component of muscles. In order to build lean muscle, you need to combine regular strength training with a diet containing adequate amounts of protein. The most important times to consume protein are during and immediately after workouts.
In a recent study, athletes who consumed a sports drink with protein during an exhaustive workout experienced 83 percent less muscle damage than athletes who had one without protein. In another study, subjects who ate protein immediately after workouts increased their muscle mass by eight percent in 12 weeks while subjects who ate the same amount of protein two hours later gained no muscle at all.
But don't overdue it. Too much protein can do more harm than good. Most women should be getting no more than 10 to 35 percent of their calories from protein, with 25 percent being a safe recommendation for many active women (for a more accurate recommendation consult a sports nutritionist).
So how do you know if you've achieved your optimal body composition? It's simple. If you're practicing these five tips and are feeling good and performing well in your sport, whatever number your body fat testing produces is perfect for you.
The American Council on Exercise offers the following guidelines for body fat percentage in women:
Matt Fitzgerald is the author of Triathlete Magazine's Complete Triathlon Book (Warner Books, 2003) and Runner's World Guide to Cross-Training (Rodale, 2004).