David, 14, stands 5’9” and weighs 131 pounds. He initially came to my office after medical tests revealed ketones in his urine. David also needed to address his frequent bouts with dizziness and premature muscle fatigue. Having recently dropped 50 pounds through an intense exercise routine that included several hours of boxing, weight training and running, David was interested in learning healthy techniques to halt his weight loss yet still allow him to gain muscle mass as he entered another growth spurt.

When the body senses its cells are not being fed properly, fat stores and lean muscle mass become a source of energy causing blood glucose levels to skyrocket and ketones (a.k.a., acetone, acetoacetic acid and beta-hydroxybutyric acid) to form within the bloodstream. In response to this “survival” mechanism, more commonly known as ketosis, the kidneys work overtime to cleanse the bloodstream excreting blood glucose and ketones in the urine generating a fruity smell often mistaken for alcohol. If left untreated, elevated ketones and glucose levels can cause organ damage, coma and even death. This month’s case study is about a high-school athlete with unhealthy levels of ketones.

Nutritional Obstacle #1:Eliminate ketones. Before I could address any of David’s performance goals, it was essential to pinpoint the cause of the abnormal level of ketones (his physician ruled out type 1 diabetes). David complained about fatigue and muscle aches, two symptoms commonly associated with a state of ketosis.

During starvation, the body slowly depletes its limited supply and preferred source of fuel (carbohydrate/glycogen) for the brain and muscles, causing a “bonking” sensation as well as precipitating premature muscle fatigue during exercise known as “hitting the wall.” As fats and lean body mass contribute more to the energy pool and ketones spill into the urine, the immune system becomes depressed, muscle wasting occurs, bone turnover increases, growth is stunted and performance declines.

Solution: A full nutritional analysis and needs assessment revealed David’s baseline or resting energy demands to be 2,350 calories with average daily expenditure with training to be 2,800 calories — well above his current average intake of 1,648 calories. A large energy imbalance is recognized by the body as “starvation” and was the cause of ketones in David’s blood.

To support David’s growth and training needs, we set his baseline calorie needs at 2,600 with additional fuel during prolonged training (an additional 300 calories per hour beyond the first hour) and post-training (400 additional calories for every hour of training completed) for recovery. We also created a custom menu plan, implementing four to six smaller meals and containing a breakdown of 55-plus percent carbohydrate, 15-20 percent protein and 20-25 percent fat. Energy dense foods (such as 100 percent juice and other liquid calories like low-fat milk or soy milk, avocados, olives and/or olive oil, dried fruit and nuts, seeds or nut butter) were included as snacks to help boost his calorie intake and support an anabolic response.

Outcome: David immediately experienced an improvement in energy levels and endurance during exercise and his ketones disappeared in his blood within a month of implementing the new nutrition program.

Nutritional Obstacle #2: Increase dietary fat intake to help support muscle growth. Research shows that very low-fat diets can lower circulating levels of testosterone. When combined with low circulating levels of insulin secondary to ketosis, muscle growth is all but a lost cause. Insulin is an anabolic hormone that facilitates glucose and amino acid transport into muscle cells thereby stimulating protein synthesis. Testosterone is a steroid hormone that is important for building muscle through promotion of protein biosynthesis. Implementation of healthful monounsaturated fats (such as olives, nuts and avocados) as well as other essential fatty acids found in flaxseed and cold-water fish (especially wild salmon) can help increase circulating levels of these hormones.

Solution: A low-fat intake is generally consistent with insufficient energy, and David’s case was no different. His custom menu included 75 grams of monounsaturated-focused fats, nearly double what he had been consuming, to support his ‘building’ goals. Sample meals from his revamped nutrition plan included old-fashioned oats topped with blueberries, flaxseed and soy milk; turkey sandwich with hummus and guacamole; grilled salmon served with sweet potatoes and mixed greens topped with olive oil and balsamic dressing.

Outcome: Over a period of four weeks, David experienced a three-pound increase in lean body mass (a 3.5-pound total weight gain).

Way to go, David!

Want more tips to help improve your fitness performance? Kimberly Mueller, M.S., R.D., founder and owner of Fuel Factor Nutrition, is a Registered Sports Dietitian and competitive athlete who provides nutrition coaching, race-nutrition guidance, and customized meal planning to athletes worldwide. More information on her services can be found at www.Fuel-Factor.com, and she can be reached at kim@Fuel-Factor.com.