Shaking up the protein myth

Walk into any health-food store and you're bound to see rows of brightly coloured tubs of protein powders that promise to help you achieve peak performance and a well muscled body. With names like Muscle Milk, CytoGainer, MyoFusion and MuscleOn you'd think these products would guarantee you a ticket to the Vancouver 2010 Olympics.

If you're serious about exercise, you're probably no stranger to protein. After all, it's the stuff muscles are made of. More protein means bigger, stronger muscles, right? Not necessarily.

Not every aspiring athlete, body builder or soccer mom needs protein shakes to help them get fit. Getting more protein than you need for exercise won't help you build bigger muscles. In some cases, those extra calories can spell unwanted weight gain.

Before you find a permanent place for a tub of protein powder in your pantry, you need to determine whether you really need it. If you do, choosing a product that's right for you can be a daunting task given the overwhelming choice in health-food stores.

Don't get me wrong. Protein is an important part of any active person's diet. Protein-rich foods such as meat, poultry, egg whites, dairy, beans and tofu supply amino acids, the building blocks used for muscle growth and repair. Getting enough protein - and calories - will help you recover from heavy workouts and allow you to train harder.

Athletes do have higher protein requirements than sedentary folks in order to repair muscle damage that occurs during exercise and to support muscle building.

Sedentary individuals require 0.8 grams protein per kilogram body weight a day. For a 190-pound (86-kg) male, this translates into roughly 69 grams of protein, an amount equivalent to 7 ounces of chicken and 21/2 cups of milk or soy beverage.

Studies suggest that endurance athletes need to consume 1.2 grams of protein per kilogram of body weight per day.

Resistance exercise such as weight lifting is thought to increase protein needs even more. It's recommended that strength athletes consume 1.2 to 1.7 grams of protein per kilogram of body weight a day.

More is not better, however. Studies have consistently shown that consuming more than the recommended amount does not lead to further increases in muscle size or strength, since there's a limit to the rate at which protein can be synthesized into muscle.

Unlike carbohydrates and fat, the body can't store protein. The excess will either be burned for energy or, if you're getting the calories you need, it will be stored as fat.

Studies also show that most athletes can easily meet their daily protein requirements from diet alone.

But some people do need protein shakes to help them meet their daily requirements. Low-calorie dieters, vegetarians, haphazard eaters and those who train very heavily may benefit from a protein supplement.

If you do use protein supplements, timing is important. Providing you're meeting your daily calorie needs, you'll build muscle more effectively if you consume protein within one hour of strength training.

According to a recent study from McMaster University in Hamilton, Ont., the optimal dose is 20 grams of protein to maximize muscle growth - an amount found in 3 ounces of meat, chicken or fish, 6 egg whites, or 1 scoop of many brands of protein powders.

It's also important to consume your post-workout protein with carbohydrates (e.g. a fruit smoothie with protein powder or a tuna sandwich). Ingesting carbohydrates triggers an increase in the hormone insulin, which helps delivers those amino acids to muscle cells.

Use the following guide to choose a protein supplement wisely.

Whey protein

The most heavily marketed protein supplement is whey, a byproduct of cheese-making. Whey protein generally contains a higher amount of essential amino acids - amino acids the body can't make on its own - than other protein sources. It also contains proteins that may help maintain immune function during intense training periods.

Depending on the processing method, there are different forms of whey protein. Whey protein isolate is the most concentrated form and contains 90 per cent or more protein and little, if any, fat and lactose.

Whey protein concentrate is less refined. It has anywhere between 20 per cent and 89 per cent protein. As the protein content increases, the fat and lactose content decreases.

On the downside, for some people whey protein can cause bloating and stomach upset.

When choosing a product, look for one that's free of artificial flavours and sweeteners. Avoid brands that contain excess sugar in the form of fructose, dextrose and maltodextrin. Pure whey protein powder should have less than 2 grams of sugar per 30 grams of protein.

Avoid spending extra money on products with added ingredients touted to maximize performance like creatine, growth peptides and glutamine. In most cases there's scant evidence to show they help and even if they do, the amount added is usually too small to provide a benefit.

Soy protein

Made from defatted soy flour, soy protein powder is an alternative for vegetarians. Products typically contain soy protein isolate, a highly purified form of soy that has the carbohydrates removed, leaving 90 per cent protein.

Like whey, soy protein also contains all essential amino acids that the body can obtain only from diet.

Studies suggest that soy protein may have benefits that extend beyond muscle repair. A regular intake of soy protein may help manage Type 2 diabetes, prevent diabetic nerve complications, increase bone density and lower LDL cholesterol. (If you're a woman at high risk for breast cancer, avoid using soy protein powders.)

Whole plant protein powders

Derived from the seeds of the hemp plant, hemp protein also supplies all essential amino acids. While it contains less protein per serving than soy, hemp protein is not refined; it also delivers naturally-occurring essential fatty acids and fibre. It can be mixed into juices, smoothies and protein shakes and added to baked-good recipes.

Vega Complete Whole Food Optimizer blends whole hemp, rice and pea proteins to boost the essential amino acid and fibre content.

Where's the protein?

Protein (grams)

Leslie Beck, a Toronto-based dietitian at the Medcan Clinic, is on CTV's Canada AM every Wednesday. www.lesliebeck.com.