Fitness and Nutrition Myths


Fitness Myths and "The Truth"
by John Berardi

I was recently asked to contribute a few fitness and nutrition myths to a popular magazine. After some consideration, I included 4 biggies - the cholesterol myth, the protein myth, the exercise volume myth, and the aerobic exercise myth.

1) The Cholesterol Myth

"Eating eggs leads to high cholesterol levels"

Adults are continually told that eating foods rich in cholesterol can elevate an individual's risks of atherosclerosis and heart attacks. As egg yolks are a major dietary source of cholesterol, this has made them public enemy #1. However, research studies consistently show that dietary cholesterol intake does not correlate well with blood cholesterol - in other words, eating foods rich in cholesterol does not necessarily increase blood cholesterol or cardiac risk. Because the body makes its own cholesterol, eating more means the body produces less. And eating less means the body produces more. It's only a small % of the population that doesn't regulate blood cholesterol well - and in these individuals, blood cholesterol can be high regardless of dietary intake. If blood cholesterol is a concern, the best way to deal with it is to increase exercise activity and improve the overall quality of your diet - not to eschew foods because they contain cholesterol.

2) The Exercise Volume Myth

"Exercising for 30 minutes 3x per week improves health outcomes."

For years we've been told that 30 minutex 3x per week was all we needed to do to improve overall health and body composition. However, according to most research, this minimal amount of activity does very little to improve either health or body composition. New government guidelines suggest that to improve health, one should shoot for 30 minutes of exercise every day. And to improve body composition 60-90 minutes a day is required. Now, before you go whining about time - North Americans plop down in front of the TV for an average of 19.8 hours per week. Surely we can make the time for 3.5-7 hours of exercise per week.

3) The Aerobic Exercise Myth

"Aerobic exercise is the best kind for fat loss."

Although aerobic exercise burns a higher % of fat per minute spent exercising, aerobic exercise alone does not necessarily lead to leaner bodies. Recent research papers with titles like "Aerobic exercise does not lead to weight loss" are demonstrating that steady-state aerobic exercise is an activity of diminishing returns - the body adapts so quickly that to really get the benefits, you'd have to keep increasing your duration - leading to sessions that would be impossibly long in duration. So the real "best" exercise for weight loss is a combination of high intensity interval exercise, strength training, and a small amount of aerobic exercise. Of course, nutrition is important too.

4) The Protein Myth

"Mega Protein builds big muscles."

Although athletes and exercisers have believed for generations that eating more protein builds big muscles, this statement isn't always true. Sure, if an individual is undereating protein (getting less than the recommended 1.5g/kg) then they might see some muscle growth with an increased intake. However, additional protein above this intake won't build more muscle. However that doesn't mean that this additional protein is a waste. In fact, additional protein intake helps improve body composition by helping maintain a higher muscle to fat ratio. Same muscle mass - less fat - sign me up!