Being lean and light is an advantage in the sport of triathlon. If proof of this obvious fact was ever needed, it came in 2011, when Swiss researchers measured the body weight and body fat percentage of 184 age-group triathletes right before they participated in an Ironman event. After the race, the researchers compared the athletes’ body measurements against their Ironman swim, bike and run times, as well as their overall finish times.
Body weight was found to have a statistically moderate effect on total race time, with lighter athletes tending to reach the finish line quicker. Body fat percentage had a large effect on total race time and a moderate effect (bordering on large) on swim, bike and run splits.
Not surprisingly, extra body weight and body fat impacted running performance more negatively than swimming or cycling performance because gravity affects running more than it affects swimming and cycling. This is why elite runners are typically smaller than elite swimmers and cyclists.
In a nutshell, this study confirmed what we already knew: It pays to be lean and light in triathlon. While some athletes are naturally skinnier than others, each athlete has an ideal racing weight that is attained when he or she has gotten rid of as much excess body fat as possible through healthy nutrition and proper training.
How much should you weigh?
Your ideal racing weight is determined primarily by your body fat level. There’s not much you can do about the other sources of mass in your body: bone, muscle, water, etc. No matter how well you train or how carefully you eat, most of that weight will stay put. It’s excess body fat that accounts for the difference between a triathlete’s current weight and his or her ideal racing weight in most instances, and thus it’s fat mass that must be lost to attain the ideal racing weight.
So, what is your ideal racing weight?
The only way to definitively determine it is functionally, in other words, by actually attaining it. By definition, your optimal racing weight and optimal body fat percentage are the numbers that are associated with your highest level of fitness. Therefore you’ll know your ideal racing weight with certainty only when you get in the best shape of your life and then weigh yourself and measure your body composition on the day of a breakthrough race.
In the meantime, however, you can create a reasonably accurate estimate of your optimal racing weight to use as a target for your weight-management efforts. Given the fact that body fat is the primary determinant of ideal racing weight, the best way to estimate it is to calculate how much you will weigh after you’ve reduced your body fat percentage to the optimal level for you. Optimal body fat percentage is not the same for everyone. There are many factors that affect how lean each individual triathlete can become.
These factors include gender, age, genetics and history of being overweight. However, even triathletes who have all of these factors working against them can get fairly lean.
The following table presents optimal body fat percentage ranges for triathlete of different genders and age groups. Most can expect to get their body fat percentage down within the optimal range associated with their gender and age group through proper training and diet.
Optimal Body Fat Ranges, By Gender and Age
Men 20-29 3-10%
Women 20-29 10-16%
It is likely that you will be able to reach the lower limit of your ideal range only if you typically lose weight fairly easily, you have never been seriously overweight and you are willing and able to maintain a high training volume. If your current body fat percentage is well above your optimal range, you should aim only to reach the upper limit of that range initially through increased training and improvements in diet.
Estimating the body fat percentage you can realistically expect to attain at your peak fitness level is not an exact science. Just use common sense and the considerations above to make an educated guess for yourself.
The next step in determining your racing weight is to calculate how much fat weight you will lose in the process of getting down to your goal body fat percentage.
Getting leaner the right way
According to a scientific survey conducted by researchers at Montana State University, more than half of endurance athletes believe they are above their optimal racing weight at any given time. This means that, if you’re like most triathletes, you are looking to shed some excess body fat before your next race. There are right and wrong ways to pursue this objective. Here are the key do’s and don’ts of performance weight management:
Do: Increase the overall quality of your diet
As a triathlete trying to shed excess body fat, you need to maintain a careful balance in your diet. On the one hand, you need to somehow reduce your calorie intake because fat loss is impossible otherwise (assuming your training is consistent). On the other hand, you need to give your body plenty of fuel to train hard and effectively. Reducing your calorie intake too much will compromise your training and defeat the purpose of losing weight.
The best way to reduce your calorie intake without compromising your training is to focus on the quality of what you eat instead of on the quantity. Calorie for calorie, foods such as vegetables, fruits, nuts and seeds, whole grains, lean meats and fish, and dairy offer greater satiety and more total nutrition than low-quality foods. So by increasing the overall quality of your diet you will reduce your calorie intake without failing to meet your body’s demands and without the need to count calories.
Don’t: Go low carb
Although the Atkins craze of the early 2000s has abated, low-carb diets remain a popular approach to weight loss. But while they can be effective, they are not a good method of weight management for triathletes because they rob the muscles of their most precious and limited source of energy for training.
Research has consistently shown that there is a direct relationship between habitual carbohydrate intake levels and training capacity. The fewer carbs an athlete consumes daily, the less training his or her body is able to absorb. Making sure you get enough carbohydrate will enable you to train better, and training better will make you leaner.
How much carbohydrate do you need? It depends on your training habits. If you train fairly lightly (less than six hours per week), aim to consume 4 to 5 grams of carbs per kilogram you weigh each day. If you train like a pro (more than 18 hours per week), you’ll need as much as 8 to 10 grams of carbs per kilogram of bodyweight daily.
Do: Monitor yourself
Among nonathletes who have lost significant amounts of weight, self-weighing is one of the best predictors of successful weight-loss maintenance. Those who weigh themselves often typically hold steady at their new, lower weight, while those who seldom step on the bathroom scale usually gain back every ounce. The reason is captured in an expression that is popular among business executives: “What gets measured gets managed.”
As a triathlete who is seeking to attain and then maintain the optimal racing weight, you should weigh yourself at least once a week and as often as daily. And since body composition is at least as important to performance as body weight, you should also measure your body fat percentage at least once every four weeks and as often as weekly. This can be done inexpensively and conveniently with a body fat scale such as a model in the Tanita Ironman series.
Finally, because there are right and wrong ways to lose weight, you should regularly monitor your performance to make sure that changes in your weight and body composition correlate with improvements in performance. Track your swim splits, bike watts and running pace in key workouts to ensure you’re getting faster as you get leaner.
Don’t: Go hungry
One of the most common misconceptions about weight loss is the idea that appetite can’t be trusted. Most people believe that if they eat as much as their tummy wants, they’re bound to overeat. Likewise, many triathletes believe that, in order to lose weight or maintain their ideal racing weight, they have to ignore their appetite and put up with a little hunger each day.
None of this is true. You can trust your appetite to guide you to the right amount of food intake. The problem is that most people today unconsciously eat more than they need to satisfy their hunger. Research conducted by Brian Wansink, author of Mindless Eating, and others has shown that it’s possible to reduce food intake without creating hunger by consciously avoiding some of the common traps that cause us to senselessly overeat.
The most common trap is the plate-cleaning instinct. People are hardwired to finish off however much food is placed in front of them (or whatever they place in front of themselves). This is a big problem today because portion sizes have increased drastically over the past 40 years. To escape the plate-cleaning trap, develop a habit of mindfully eating until you are comfortably full and then stopping, even if there is leftover food on your plate that must be saved until later. Once you’ve developed a better sense of how much food you really need to satisfy your appetite, you can then adjust the amount of food you prepare and serve yourself at home and the amount you order when eating out so that the temptation to overeat is further reduced.
Do: Practice nutrient timing
When you eat is almost as important as what you eat in the quest to get leaner. You should take in the most calories at those times when your body’s energy needs are greatest and take in the least calories when your body’s immediate energy needs are lower. If you do this consistently your body will put food calories to the best possible use—building and refueling your muscles instead of adding to body fat stores—and you will become leaner than you would if you ate the same number of calories each day but at the wrong times.
Your body needs the most energy when you first wake up in the morning, when you haven’t eaten in 10 or 12 hours, and after workouts, when your muscle fuel stores are depleted. Energy needs are much lower in the evening and when you’re doing desk work. With this idea in mind, concentrate your daily calorie intake in the morning and post-workout periods, and eat lighter at other times.
Don’t: Train for fat loss
As important as a lean body composition is in triathlon, you should not train with fat loss as your primary goal. Instead you should train for maximum performance. Most of the fat-loss exercise programs offered by personal trainers and fitness gurus place a heavy emphasis on high-intensity intervals. This type of program can be an effective way to shed excess body fat, but it is only appropriate for nonathletes who perform cardio workouts only a handful of times per week. It is not appropriate for triathletes who swim, bike and run at least six and up to 12 times per week. If you try to incorporate too much high-intensity interval work into your training, you will become chronically fatigued and your fitness will stagnate.
Research has consistently shown that endurance performance improves most when athletes follow the 80-10-10 Rule, doing about 80 percent of their training at low to moderate intensities, 10 percent at a moderately high “lactate threshold” intensity and 10 percent at high intensities. What’s more, form tends to follow function in endurance training. So when you heed the 80-10-10 rule you will become leaner as you become fitter.
A Quick Start
It’s not possible to maximize fitness development and fat loss at the same time. That’s because the actions that are required to maximize fat loss—particularly substantial calorie restriction—limit the body’s capacity to train and adapt to training. So when you’re preparing for an upcoming race it’s important that you make fitness development your clear top priority and train and eat accordingly. You will get leaner as your race approaches, but probably not as quickly as you would if you were totally focused on fat loss.
There is a proper time to make fat loss your first concern, and that’s during a four- to eight-week period before you start the process of building your fitness for a race. I refer to these brief periods of intensive fat loss as “quick starts” because their purpose is to give you a quick start toward your optimal racing weight. Within a quick start, your diet and training should be different than they are within the race-focused training cycle in five key ways.
1. Moderate caloric deficit
Aim to consume 300–500 fewer calories per day than your body burns. This moderate caloric deficit is big enough to yield fairly rapid fat loss but not so big that you will be lethargic or constantly hungry or lose muscle mass.
2. Higher protein intake
Try to get 30 percent of your daily calories from protein within the quick start. (The typical American diet is 18 percent protein.) Eating more protein while eating less overall will help you avoid hunger and prevent muscle loss.
3. Gym work
I recommend that triathletes perform three full-body strength workouts per week in quick-start periods. This will ensure that you hold onto your lean muscle mass and lose only fat.
4. Power intervals
Once a week, do a set of very short (10–20 seconds) sprints at maximum intensity in each of the three triathlon disciplines. This type of training stimulates a lot of post-workout fat burning through an effect known as excess post-exercise oxygen consumption (EPOC).
5. Fasting workouts
Every other week, do a long bike ride early in the morning without consuming any carbohydrate before the workout or during the ride. (Do consume water, or water plus electrolytes during the ride, though.) In alternate weeks do a fasting long run. This type of moderate intensity training enhances general fat-burning capacity during exercise, which increases raw endurance and reduces the likelihood of bonking in longer events.