Metrics in Motion
How to use body composition metrics to plan your nutritionAugust 4, 2011
Photo by dno1967b
In January you read A Better Way To Evaluate Body Composition, which covered how to use metrics to determine your optimal goals for body composition. In that article, Jesse discussed body fat percentage and Body Mass Index (BMI), which, when used in conjunction, produce an effective sport-specific metric–the sum of these being more insightful than either of the individual parts alone. Here I will attempt to take the natural next step by outlining the dietary changes we can all make to reach our goals. But as we all know, the road to our race weight goals (for an event that is some time down the road) is not necessarily always a straight one.
All of our QT2 Systems athletes train under a one-on-one, fully customized periodization plan. Each is paired with a dietitian who works with the coach to determine their dietary needs, based upon their specific limiters, training volumes, and training intensities. This relationship is the basis of how an athlete’s body composition goals dovetail with their performance goals. Each plan defines a development of gradual stress and super-compensation, which progresses from non-sport-specific activities, to those that are very race specific. The gradual application of stress is the result of a careful combination of increased volume and intensity. For every three to four weeks of increasing stress, there is a week spent allowing the body to adapt to and absorb these stressors. Your dietary needs to follow a course parallel to that of your training.
So, how does all of this happen?
Identifying Specific Limiters
Firstly, you and your coach must identify your specific limiters and physiological needs. These, when considered alongside your A-race, will help to define your specific periodization plan. Don’t forget to take into consideration any key races and important training sessions, which are planned along the way. This is also the perfect time to determine your current body fat percentage and BMI. Once these are established you can set BF percentage and lean-adjusted BMI goals through different points in your training.
The Base Phase
Along with your A-race distance, your coach should consider your physiological fingerprint in determining the length of your base phase. Most good training plans will incorporate a cycle of formal strength work during the base phase. This is the prime time for you to consider the role that your lean adjusted BMI will play in your diet. A low lean-adjusted BMI athlete will likely be strength limited, especially as it pertains to the bike, and should actually be assigned both a protein and caloric surplus. This creates an anabolic atmosphere where lean muscle mass can grow and flourish. In this case, protein intake may be as high as one gram per pound of body weight per day, with a 200-calorie surplus. As a result, you may begin to see body weight climb, as muscle is naturally heavier than fat.
On the other hand, a high lean-adjusted BMI athlete may have more muscle mass than their aerobic system can effectively utilize, and may want to operate under a much lower protein and calorie requirement in order to strip some of that excess muscle. (It is strongly recommended that you seek the advice of a Registered Dietitian before following either path.) During this time, body fat percentage is the preferred metric, as an increase in weight coupled with a decrease or stagnation in body fat is indicative of an increase in muscle mass.
Many triathletes begin their training with 10 or more pounds of extra weight. In a panic, many will try to shed this weight as quickly as possible, but it’s often important to maintain at least some of this weight as a basis on which to build lean muscle mass. Weight loss during this initial base phase may not be a primary focus—the goal should be to complete the base phase of training no more than 10 pounds above the intended race weight.
Mid-Training Build Phases
Following the base phase comes the build phases of training, where we increase the stress (volume and intensity). At the beginning of this stage, caloric requirements increase only slightly above those in the base phase. But as the training becomes more and more sport-specific, with increasing duration and intensity, additional carbohydrates are needed to fuel the activity. Despite the additional carbohydrates, an appropriate amount of protein is still needed to maintain lean muscle mass.
This is the point in training when you often hear athletes say “I’m training for an Ironman, so I can eat anything that I want.” The increase in intensity can be very deceiving, and must be carefully managed on both the training and nutrition fronts. Macronutrient management during these initial weeks can be easily misunderstood, as protein levels should be maintained but carbohydrate increases will likely be fulfilled with training and recovery fuels. Carbohydrates consumed outside of an appropriate workout window can quickly accumulate unwanted body fat during these first weeks of intensity.
As you get deeper into these build phases, and both the intensity and volume of your training increase, it is vitally important that your caloric intake increase as well. This requires that careful attention be paid to your periodization plan to assure that your training and diet are parallel. Just as an increase in volume and intensity should be met with an increase in calories, a recovery week should see a similar reduction. With less volume and intensity, fewer carbohydrates are needed. It is a delicate balance that must be played from week to week to ensure that the required caloric levels are being met with appropriate macronutrients. Body fat percentage, again, acts as the most reliable metric as it effectively tracks any progress in this area.
Approximately four to six weeks prior to an A-race, QT2 athletes will enter into an overload period of training. (The exact timing is typically dependent upon the nature of the race distance and the athlete’s volume.) This is the two or three-week period where both volume and fitness will be at their highest. It is very taxing on the body, and will definitely require a dietary response, primarily in the form of increased carbohydrates to cover the additional training volume. A failure to meet the volume demands with an appropriate level of carbohydrates will leave you feeling lethargic before, during, and after your workouts. Recovery from your workouts is also likely to be compromised, which leads to sub-par workouts on subsequent days—a vicious cycle!
This is an excellent time to evaluate your body fat percentage relative to where you have set your race goals. At this point there is just enough time before your A-race to make the necessary adjustments in terms of those goals. Whether you need to be a bit tighter with your intake, or are already at race weight, this assessment is imperative to maximizing your speed potential on race day. It’s preferable to be within two to three pounds of your race weight at this point in your training. If you’re above, you should consider being a bit more aggressive with your calorie deficits outside of training. If you’re below, you may want to be a bit more indulgent as it’s very difficult to maintain your race weight for much more than three weeks without significant systematic stress.
Newton’s first law of motion, “An object in motion tends to remain in motion,” also applies to triathletes. The taper can be a frustrating time for any athlete, from both nutritional and dietary standpoints. The reduction in volume required by the taper can shock your system, especially following the massive volumes of your peak training. It’s a necessary evil, however, so that you can enter your A-race as rested and fit possible.
Your appetite can be just as vulnerable to Newton’s laws as your training. During the taper period of your training you have to be very careful of unwanted weight gain. The tendency in your taper is to eat as you did during the build and peak phases of your training. Depending on where you are in your body composition, you will have to scale your caloric intake accordingly. With race day approaching you should be within one to two pounds of your goal race weight. Because your body composition goals are meant to maximize performance, they may not be very comfortable or well regulated by the body for extended periods of time. As such, the closer to race day that these goals can be achieved, the less risky they becomes to performance and your immune system.
During this time, body fat percentage should be monitored very, very closely. If it dips too low, too soon, there is a very acute risk of suppressing your immune system. At the same time, too much of a calorie surplus in these final few weeks can lead to a last minute increase in weight. This body composition balancing act must be played within the confines of your periodization plan. Caloric intake must parallel your training volumes and intensities throughout your entire training program, but especially during the taper.
The combination of body fat percentage and BMI can act as a very powerful tool when used properly. Understanding your BMI at a particular body fat percentage allows you to determine your lean-adjusted BMI. Do you need more muscle mass for your sport? Is too much muscle actually slowing you down? The answers to these questions will determine the nature of your strength work and dietary intake.
Once the characteristics of your training and dietary intake have been established you can then use body fat percentage to track your progress as you make your way through your training. Remember that just as a well-developed training plan will use sensible periodization principles, your dietary plan will require similar attention. During heavy periods of training you’ll require greater amounts of calories, especially from carbohydrates, to fuel your workouts. Carbohydrate and caloric intake during recovery weeks will need to be diminished proportionally. Proper management of these details will ensure that you approach each day of your training well fueled, properly recovered, and without unwanted body fat.
Anne Rollins is a registered dietitian working with triathlon coach Jesse Kropelnicki and TheCoreDiet.com and QT2Systems.com. She holds a bachelors and masters degree in nutrition. TheCoreDiet is a sports nutrition specialty group working with athletes from age groupers to world class professionals. Visit their website to explore how they can add a nutrition component to your coaching business and help your athletes achieve better body composition, health, and performance goals.