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Weight Matters: Know when to lose weight and when to get fit

Triathlon Magazine Canada nutrition

Triathlon Magazine Canada nutrition
by Matt Fitzgerald

My brother Sean is a gifted runner whose main limitation has always been his size – he’s six-foot-three and usually weighs over 200 pounds. Recently he trained hard to take a crack at improving his marathon PB of 3:02. Three weeks before the race he was in great shape, but still heavier than he wanted to be. So he put himself on a strict diet and lost five pounds before race day. But his marathon was a disaster – he felt terrible from the start and struggled to a 3:27 finish.

Sean’s mistake is common among triathletes. He tried to tackle fitness gains and fat loss simultaneously. Both fitness and a lean body composition are important to success in endurance sports. Chances are you need to increase your fitness level and shed some body fat to achieve your goal in your next triathlon. But, if you do what it takes to maximize fat loss – namely, reduce your food intake – you will deprive your body of the energy it needs to handle increasing training loads and thereby sabotage your fitness development.

A 2009 study conducted by researchers at Southern Connecticut University showed cyclists who reduced their food intake by 500 calories per day improved their “power-to-weight ratio” (a reliable measure of cycling performance capacity) by losing weight and keeping training consistent. Cyclists who kept their diet the same, but added high-intensity intervals to their training, improved their power-to-weight ratio equally by maintaining their weight and gaining fitness. But cyclists who reduced their food intake and added intervals to their training simultaneously failed to improve their power-to-weight ratio because they were robbed of the energy they needed to benefit from the harder training.

Endurance athletes are better off prioritizing fat loss independent of fitness improvement during a brief period (four to eight weeks) that immediately precedes the start of a ramp-up for racing. But even then you need to pursue fat loss in a way that accommodates your current training needs and respects your future race plans. A motivated nonathlete can lose weight by skipping lunch every day. You shouldn’t.

So what should you do during your four- to eight-week fat-loss phase? I recommend aiming for a daily energy deficit of 300 to 500 calories. That’s large enough to stimulate a significant amount of fat loss in four to eight weeks but not so large as to sabotage your training. I further suggest that you increase your protein intake to about 30 per cent of total calories during this period. This will reduce the amount of hunger that attends you calorie reduction and – when combined with strength training – ensure that you don’t lose muscle mass.

As for training, a fat-loss focus period is a good time to prioritize strength training. Do at least two and ideally three full-body strength workouts per week. Not only will this ensure that all of the weight you lose is body fat but it will also reduce your chances of getting injured after you transition to racefocused training. A fat-loss focus period is not the time to log heavy mileage. But there are a couple of types of workouts that will promote fat loss without high overall volume at this time. One is power intervals – repeated maximal efforts lasting just 10 to 20 seconds. This type of workout promotes fat loss by keeping the body’s metabolism elevated long after the session is completed. Do one set of power intervals per week in each discipline throughout your fat-loss focus period.

Another effective workout for fat loss is the fasting workout, which is a relatively long, low-intensity session that follows a low-carbohydrate meal (or no meal) and during which you consume no carbs. Depriving your muscles of carbs in a long workout maximizes fat burning. Do one fasting workout per week, alternating between bike rides and runs, throughout your fat-loss focus period.

When you transition out of your fat-loss focus phase and into race preparation, you can, and should, continue to lose excess body fat, but not as quickly, because your training and diet habits will shift to support fitness building. In terms of diet, concentrate on quality instead of quantity. High-quality foods are vegetables, fruits, nuts and seeds, whole grains, lean meat and fish, and some dairy. Eat as much of these foods as you like. Low-quality foods include refined grains, fatty meats, sweets and fried foods. Eat these foods sparingly. By maximizing your diet quality you will be able to shed excess body fat without compromising your training and reach the next starting line at your optimal racing weight.