Optimal Eating

A registered dietitian is your best friend when it comes to suggesting dietary changes to your clients, but you can help them stay nourished around their sessions. Clients’ nutrition goals are as varied as their exercise programs. The chart on page 59 offers ideas that will produce optimal effects before, during and after your clients’ favorite exercise routines.

Hydration Guidelines

In addition to a nutritious diet, adequate fluid is essential for the physical activity your clients perform. Dehydration can lead to potentially serious side effects, such as increased core body temperature, elevated heart rate, decreased blood volume and diminished physical performance (Robergs & Roberts 1997). The human thirst mechanism is fairly ineffective; therefore, planning when and what to drink is the best defense against dehydration. The American College of Sports Medicine (ACSM) recommends approximately 16 ounces (oz) (2 cups) of fluid 2 hours prior to exercise and 4 to 8 oz immediately before to ensure adequate fluid levels and time to excrete the excess (ACSM 2000; Kleiner & Greenwood-Robinson 1996). Add another 12
to 20 oz 1 hour before exercise in warmer temperatures (Kleiner & Greenwood-Robinson 1996).

During intense exercise or exercise in a hot, humid environment, the body can lose up to 2 to 3 liters per hour (Robergs & Roberts 1997). Be sure clients replenish their fluids during activity; 6 to 12 oz every 15 to 20 minutes is optimal (ADA 2000). Drinking a carbohydrate or electrolyte
solution may hasten absorption (Robergs & Roberts 1997).

A carbohydrate beverage (e.g., sports drink) during exercise provides added benefits as intensity increases. It provides the glucose necessary to ward off early fatigue and promote fluid consumption (Robergs & Roberts 1997). Advise clients to avoid fruit juice and soda because their high carbohydrate concentrations can delay fluid absorption and cause stomach distress (Robergs & Roberts 1997). Suggest a beverage containing approximately 14 to 16 grams of carbohydrates and 120 to 170 milligrams of sodium per 8 oz—although sodium is not necessary unless the exercise lasts longer than 4 hours (Kleiner & Greenwood-Robinson 2001; Clark 1997).

The best strategy to ensure proper hydration is to check body weight before and after exercise and consume 20 oz for each pound lost (Kleiner & Greenwood-Robinson 2001). Another method is to monitor urine color. A “light lemonade” color is preferred over “Mountain Dew®.” Lastly, following exercise avoid alcohol, because of its diuretic effect.

Regardless of their workout goals, your clients need ample carbohydrate storage and replenishment. While it is not within a personal trainer’s scope of practice to plan meals for clients, you can offer suggestions based on the Food Guide Pyramid. Provide clients with ideas customized for their favorite workouts, and exercise goals will be easier to attain.