Cyclingnews Fitness Q&A - February 1, 2012

The peloton tackle the heat and wind at the 2011 Tour of Qatar (Image credit: Bettini Photo)

Topics: Food intake/Nutrition, Power differences in pedal strokes, 10 mile time trials

Although each athlete's training diet should be individualized to meet their particular needs, a few general principles apply. Obviously, if you want to lose body fat, you must expend more energy than you consume. You can accomplish this both by increasing your training volume and/or intensity and by reducing your energy intake. However, you do not want to short change your body on the fuels needed for training or on the nutrients needed for recovery and training adaptation.

If you are regularly(i.e., multiple times per week) training for more than 90 minutes at a time at moderate-to-high intensity, you need to be sure to be sure that you are eating enough carbohydrate. Here’s the reason that dietary carbohydrate is essential for endurance athletes who train for prolonged periods of time. Our bodies prefer to use carbohydrates and fats (not protein) for energy during exercise. At rest or during low-intensity exercise (<50% of VO2max), the preferred fuel is fat. This fat can come from our diets if we've just eaten or from our fat stores if we're between meals. As exercise intensity increases, our bodies have to shift from fat to carbohydrate to generate energy.

At maximal exertion, we use only carbohydrate. In situations where oxygen demand is high (i.e., high-intensity exercise), carbohydrates have an advantage over fats because less oxygen is required to produce a given amount of energy. Dietary carbohydrate is important because the carbohydrate stored in our bodies as glycogen in the liver (240 kcal) and muscle (1400 kcal) is in limited supply. When our glycogen is gone (usually after 1.5-2 hours of exercise), we literally run out of fuel and have to markedly decrease our exercise intensity (i.e., switch back to using fat).

There are two strategies to prevent depletion of glycogen during
exercise: start with “full” glycogen stores and consume carbohydrate during exercise. To maintain glycogen stores, endurance athletes should consume 6-10 g of carbohydrate per kg of body weight (target body weight) in their usual diet. The pre-training meal should provide 100-300 g of carbohydrates, depending on workout duration and intensity. During a training ride of >90 minutes, the recommended intake is 30-60 grams of carbohydrate per hour. Drinking 16-32 ounces of a commercial fluid-replacement beverage that contains 4-8% carbohydrates every hour would meet this guideline. Most energy gels contain about 25 g of carbohydrate, and these work fine as long as they are taken with water to avoid gastrointestinal distress.

Carbohydrates that are easily digested and absorbed, i.e., high glycemic index, will allow for rapid repletion of muscle and liver glycogen. Exercise increases the rate of protein breakdown and synthesis in skeletal muscle and, with adequate nutrition, it can have an anabolic effect on skeletal muscle. Carbohydrate consumed post-exercise is beneficial because it reduces the rate of protein degradation.

Correcting such an imbalance is a many-month process. If there is a significant difference in strength, start by working on that by doing workouts that are challenging for the weaker leg but easy for the strong leg. if you have a lazy leg rather than a weak leg, it is often possible to correct it by such simple maneuvers as focusing on the weaker leg by counting cadence on the down-stroke on that side.

Again, assuming you are well trained for road racing, there's not much fitness change you are going to accomplish as you prepare to TTs. Rather, you need to dial in your pacing and gearing strategies. Ideal pacing for a TT allows you to maintain power the whole time, with near exhaustion at the end. Since you are doing the training on rollers, you don't need a power meter to tell you if you are making steady power or not since power and speed correlate perfectly on rollers.

Scott Saifer (www.wenzelcoaching.com) is head coach, CEO of Wenzel Coaching.com and has been coaching cyclists professionally for 18 years. He combines a master's degree in Exercise Physiology with experience in 20 years of touring and racing and over 300 road, track and MTB races to deliver training plans and advice that are both rigorously scientific and compatible with the real world of bike racing.

Steve Hogg has owned and operated Pedal Pushers since 1986, a cycle shop specialising in rider positioning and custom bicycles. In that time he has positioned riders from all cycling disciplines and of all levels of ability with every concievable cycling problem. Clients range from recreational riders and riders with disabilities to World and National champions. He can be reached at: www.stevehoggbikefitting.com

Carrie Cheadle, MA (www.carriecheadle.com) is a Sports Psychology consultant who has dedicated her career to helping athletes of all ages and abilities perform to their potential. Carrie specialises in working with cyclists, in disciplines ranging from track racing to mountain biking. She holds a bachelors degree in Psychology from Sonoma State University as well as a masters degree in Sport Psychology from John F. Kennedy University.