Dr. Susan M. Kleiner, PHD, RD, FACN, CNS, FISSN • High Performance Nutrition

Frequently Asked Questions


Are sports drinks superior to water?

In some cases — yes. For general types of exercise lasting less than one hour, water is still the best sports drink around. The nutrient you most need to replace during and after these types of workouts is water.

Carbohydrate-replacement beverages and glucose-electrolyte solution drinks (also known as sports drinks) do have their place — mostly for high-intensity intermittent exercise, for exercise lasting more than 45 minutes, and especially for use by endurance and ultraendurance athletes. These products are a mixture of water, carbohydrate, with or without electrolytes. Electrolytes are dissolved minerals that form a salty soup in and around cells. They conduct electrical charges that let them react with other minerals to relay nerve impulses, make muscles contract or relax, and regulate the fluid balance inside and outside cells. In hard workouts or athletic competitions lasting 60 minutes or longer, electrolytes can be lost through sweat. Carbohydrate-only beverages are great for replacing fuel losses during intense exercise when electrolyte losses are not high. Athletes training for hours, and certainly ultraendurance athletes should consider electrolyte replacement as well as carbohydrate and fluid replacement during long-duration exercise.

Where glucose-electrolyte solutions may have an edge over water during exercise of only short duration is in their flavor. A lot of people just don't drink much water because it doesn't taste good. When soldiers participating in a study at the U.S. Army Research Institute of Environmental Medicine were given the choice of drinking plain chlorinated water, flavored water, or lemon-lime glucose-electrolyte solution drinks, most chose the glucose-electrolyte solutions or flavored water over plain water. One way to sneak more water in and still get the flavor is to dilute your glucose-electrolyte solution or use one of the flavored low-calorie waters.

For those of you who train hard for longer than one hour, you need to refuel during training. Along with hydration, sports drinks help you refuel. There are many products on the market, and the marketplace continues to change with new products nearly every week. Investigate the research behind  products before you believe everything the manufacturer promises.


Can I still build muscle if I'm a vegetarian?

Absolutely! Whether to include or exclude meat in your diet is a matter of personal choice. If you decide to go meatless, plan your diet carefully to avoid certain nutritional danger zones-namely iron, zinc, and B12 deficiencies. These deficiencies can hurt exercise performance. Here are some tips for avoiding deficiencies if you're a vegetarian strength trainer.

Get Enough Protein
Make sure to get in the 2.0-2.5 grams of high-quality protein per kilogram of body weight (0.9-1.1 grams per pound) required daily to support muscle growth. You can do this by including plenty of low-fat dairy products and protein-rich plant sourcesin your diet. If you are a pure vegan , increase your protein intake an additional 10% to meet the increased requirement due to digestibility differences.

Include Some Heme Iron Sources
All types of animal protein contain the more easily absorbed form of iron, heme iron. If you're a semi-vegetarian-that is, still eating fish or chicken but no red meat-you're in luck. Chicken and fish contain heme iron. Vegetables contain only non-heme iron, that is less well absorbed by the body compared to heme iron from animal sources.

Watch the Meat-Fish-Poultry Factor
Meat, fish, and poultry (MFP) also contain a special quality called the MFP factor that helps your body absorb more non-heme iron. When meat and vegetables are eaten together at the same meal, more non-heme iron is absorbed from the vegetables than if the vegetables had been eaten alone. If you're a semi-vegetarian, your body will absorb extra iron from vegetables.

Include Vitamin C Sources
Fruits, vegetables, and other foods that contain vitamin C help the body absorb non-heme iron. For example, if you eat citrus fruits with an iron-fortified cereal, your body will absorb more iron from the cereal than if it had been eaten alone.

Guard Against a B12 Deficiency
Vitamin B12 is one of the most significant nutrients typically missing from the diets of vegans. That's because vitamin B12 is available only from animal products. Fortunately, the body needs only tiny daily amounts of the vitamin. The DRI is 2.4 micrograms for adults. Vegans should eat B12-fortified foods and take supplements to ensure a healthy diet.

Watch Iron and Zinc Blockers
Some foods contain phytates, oxalates, or other substances that block the absorption of iron and zinc in the intestine. Coffee and tea (regular and decaf), whole grains, bran, legumes, and spinach are a few examples of foods containing blockers. These foods are best eaten with heme iron sources or vitamin C sources to help your body absorb more iron and zinc.

Consider Iron and Zinc Supplements
Our bodies don't absorb the iron that comes from vegetables as easily as the iron that comes from animal foods. Nonmeat eaters, especially active people or menstruating women, must pay attention to their dietary iron needs.

Animal flesh is the major source of zinc in our diets. So all styles of vegetarian eaters may be at greater risk of having marginally low intakes of this mineral.

Although dietary supplements are not as good as food, it may be a good idea to supplement if iron and zinc are in short supply in your diet. Daily supplementation of iron and zinc at the level of 100 percent of the DRI is good insurance against harmful deficiencies.

How much protein do I need to build muscle?

With increases in training intensity, you need additional protein to support muscle growth and increases in certain blood compounds. On the basis of the latest research with strength trainers, I recommend that you eat 2.0-2.5 grams of protein per kilogram of body weight (0.9-1.1 grams per pound) a day, depending on your gender and level of training. Here's how you would figure that requirement if you weigh 150 pounds or 68 kilograms:

2.0 g protein x 68 kg =  136grams of protein per day.
0.9 g protein x 150 pounds =  135grams of protein per day.

Strength trainers living in high altitudes need even more protein: at least 2.2 g per kg (1.0 g/lb) of body weight daily. And, vegan vegetarians should take in an additional 10% more protein above their calculated need a day to make sure their diets are providing all the amino acids their bodies require.

Are you a brand new strength trainer? If so, you may need to eat more than a veteran strength trainer typically consumes — as much as 40 percent more.

You can find specific formulas personalized to your needs in my latest book: Power Eating, Fourth Edition

Power Eating



I know that I need to eat more fiber, but I don't like the way I look and feel
when I get gassy. Do you have any suggestions?

Stick to a regimen of smaller multiple meals that include carbohydrate, protein and fat. These small frequent meals give you timed-release energy while lowering the total volume of fiber you take in at any one time. Also, the friendly bacteria  in your gut feeds off fiber. A by-product of bacterial digestion can be gas, but if you take in fiber in smaller amounts, less gas is produced.

Some people produce less gas from vegetables and fruits compared to grains. Others react specifically to certain vegetables or fruits. High intakes of sugar can result in gas and discomfort due to the resulting higher fructose consumption. Some level of fructose intolerance is not uncommon, especially if consumed immediately before exercise. Pay attention to whether specific foods promote more gas and intestinal upset, and limit those foods in your diet. If you have trouble with bloating, the following list includes the high-fiber foods that form the least gas.

  • Fresh fruits with skin
  • Dried fruits
  • Fruit juices with pulp
  • Potatoes, sweet potatoes, and yams with skin
  • Peas
  • Carrots
  • Winter squash
  • Tomatoes
  • Romaine, leaf, Boston, and bibb lettuces
  • Whole grains and cereals, particularly buckwheat, oatmeal, bulgur wheat and semolina

What should you eat and when?

The key is to time your meals around your workout schedule. In a nutshell, exercise and food intake work in concert to build lean muscle. The table below provides a step-by-step look at how to time your meals properly and the benefits of doing so. For more detailed information see my book, Power Eating, Fourth Edition (Human Kinetics, 2014). 

Power Eating


Throughout the Day

  • Fluids: 8 to 12 glasses a day. At least 5 cups should be pure water.
  • Breakfast: Never skip this meal since it improves physical and mental performance, plus helps regulate weight.
  • Meals: Small, frequent protein/carbohydrate meals and snacks every 2 to 3 hours.

Before Exercise

  • Fluids: At least 8 ounces prior to exercise.
  • Pre-Exercise Meal: At least 4 hours prior to exercise so that the body properly assimilates carbohydrates for use by muscles.
  • Pre-Exercise Snack: 30 to 90 minutes prior to exercise. Snack should consist of 200-400 calories, including 30-50 grams of carbohydrate, plus 10-20 grams protein, and not more than 5-7 grams of high performance fat. Snack can be food or meal replacement supplements. These will provide additional energy for prolonged stamina and help decrease exercise-induced breakdown of muscle protein.

During Exercise

  • Fluids: 7 to 10 ounces every 10 to 20 minutes.
  • Carbohydrate-replacement or glucose-electrolyte sports drinks: Sipping these during a workout has been shown to extend endurance. Use them during phases when you’re trying to build muscle but not when you’re trying to lose fat.

After Exercise

  • Fluids: Replace each pound of fluid lost with 16 to 20 ounces of water or sports drink.
  • Carbohydrates: Consume 0.5-1.0 g/kg depending on what phase you’re in.
  • Protein: Consume 0.5 g/kg protein with carbohydrate to encourage muscle growth. Post exercise snacks can be in the form of meal replacement beverages with 0.5 to 1.0 g/kg carbohydrate and 0.5 g/kg protein.  Follow this by a meal within 2 hours of exercise containing lots of unprocessed carbohydrate and high quality protein sources (fish, lean meats, low-fat dairy products, eggs, etc.)

If you could tell me one magic thing to do with my diet to help
with my training, what would it be?

Try two great recipesfor Post-exercise recovery drinks below, and get more energy-boosting recipes in
Power Eating, Fourth Edition (Human Kinetics, 2014)

For information about USANA Health Sciences, Inc., go to www.drskleiner.usana.com

Power Eating

Post-exercise Recovery Drink Recipes

Almond Peach

Combine the following ingredients in a blender, blend on high speed, and enjoy!

Makes 1 serving.
One serving contains (includes almond milk):

  • 1 cup (240 ml) water or almond milk
  • 1 cup frozen peaches
  • 1 tbsp (16 g) nut butter
  • 1 tsp (2.4 g) cinnamon
  • 2 scoops USANA Smart Shake (protein of your choice: whey, soy or plant)


Apple Ginger Spinach Berry

Combine the following ingredients in a blender, blend on high speed, and enjoy!

Makes 1 serving.
One serving contains (includes apple juice):
  • 1 cup (240 ml) all-natural 100% apple juice
  • 1 tbsp fresh chopped ginger (approx. 1 in., or 6 cm, piece)
  • 2 cups (56 g) baby spinach
  • 1/2 cup (72 g) fresh or frozen blueberries
  • 2 scoops USANA My Smart Shake (protein of your choice: whey, soy or plant)
  • 1 USANA My Smart Shake Chocolate Flavor Shot


What do you think of creatine for strength trainers?

Quite probably, creatine is the most important natural fuel-enhancing supplement yet to be discovered for strength trainers. Unlike a lot of supplements, creatine has been extensively researched, with more than 500 studies conducted to date. Of these studies, 300 have focused on the performance-enhancing value of creatine, and about 70 percent of these studies report positive effects.Exciting experiments show that creatine produces significant improvement in sports that require high levels of strength and power, including strength training, rowing, and cycling sprints. Another big plus for creatine: Several creatine supplementation studies have shown gains in body mass averaging 2 to 5  pounds during 4 to 12 weeks of training. It was once thought that this increase was mostly water weight gain. But now we're seeing that a significant amount of the gain is pure muscle, and only a small portion is water.

How It Works
You "load" creatine into your muscles, just like endurance athletes do with carbs. Consequently, you can push harder and longer in your workouts because creatine boosts the pace of energy production in your muscle cells. Creatine supplementation doesn't build muscle directly. But it does have an indirect effect: You can work out more intensely, and this translates into muscle gains.

How Much?
Creatine usually comes in a powdered form as creatine monohydrate. The latest scientific research shows that the most rapid method of increasing muscle creatine stores is to consume approximately 0.3 gram per kilogram of body weight per day of creatine for at least three days, followed by 3-5 grams of creatine per day thereafter to maintain elevated stores. Ingesting smaller amounts of creatine, 2-3 grams per day, will increase muscle creatine stores over a 3-4 week period.

Because creatine levels will be maintained in your muscles for about 3 weeks, another strategy is to cycle on and off creatine rather than using the loading maintenance phases. Start with a dose of 5 grams per day for about 6 weeks. It will take a little longer to reach saturation levels compared to the loading dose, but the results are virtually the same. Cycle off the creatine for about 3 weeks, and then go back on it again. Your muscle levels and training results will remain high during the off period. This strategy will lighten the strain on your wallet, while still giving you competitive results.

The logic that if a small dose is good, a large dose is better isn't a good idea. The body has a ceiling on the amount of creatine that it will store in the muscles. If you keep taking more, creatine will not continue to load in the muscles.

While loading with creatine, make sure to drink extra water. This may control any cramping that may occur. And you're asking for trouble if you belt down daily dosages of 40 grams or more. Such high doses may cause possible liver and kidney damage, according to some reports. Before trying any supplement, you should make sure that your diet, your training, and your rest is the best that they can be. No supplement can replace food, training, or rest. I also don't recommend creatine for adolescents. With the benefit of growth on your side, the use of creatine should be unnecessary. Check with your physician before supplementing with creatine.

You will find more information on creatine supplementation and products in
Power Eating, Fourth Edition

Power Eating

I travel a lot and need to eat fast food. What is the best place
to get healthy choices?

These establishments are a step ahead of the competition in offering healthy choices. This is a list of my newest top 10 (alphabetical order), but many of the restaurants are trying to change to healthier menu offerings and they make the nutritional information easily available to customers.
In Power Eating, Fourth Edition, I list my “best food choices” at each of these restaurants.

Top 10 Restaurants
For On-the-go Eating
  1. Au Bon Pain
  2. Chipotle
  3. Einstein Brothers Bagels
  4. McDonald’s (Yes, really.
    Sometimes it’s the only place you’ve got)
  5. Noah’s Bagels
  6. Panera Bread
  7. Qdoba
  8. Subway
  9. Taco Del Mar
  10. Wendy’s

Here are the keys to better choices:
  • Broiled not fried.
  • Avoid sauces, and add your own condiments with portion control.
  • Keep salads light.
  • Choose regular sized potions, not super sized.
  • Limit your sandwich to 2 slices of bread.
  • Drink water or milk, not sugary drinks.
  • Pack fruit for dessert rather than choosing a high-fat, high-sugar dessert.

Power Eating

How much carbohydrate do I need to fuel my workouts?

The amount of carbohydrate you need in your diet each day varies, depending on your training goals, how frequently and intensively you train, your gender, and your own individual needs. After decades of working with athletes at all levels and in all kinds of sports, I have noted that carbohydrate is needed in highly variable amounts from one individual to another even doing the same level of exercise. In general, to fuel performance, athletes need from 4.5 to 10 grams of carbohydrate per kilogram of body weight every day. This very large range depends on the factors noted earlier, including the type of exercise, exercise goals, the frequency, intensity, and duration of exercise, gender, and the weight requirements of the sport. Carbohydrate needs are different still when the goal of the diet and training program is to lose fat.

That discussion, as well as customized menu planning guidelines, can be found in Power Eating, Fourth Edition.

Power Eating