Common Fitness Questions Answered
What Caused the Obesity Epidemic and What is the Ideal Racing Weight?
My day job is in the fitness industry, and occasionally I write about health and fitness topics. I figured I'd put together a quick summary addressing common fitness and nutrition topics. Take this as general advice. It won't apply to everyone. It won't apply to serious athletes. But it will apply to the majority of Americans.
At my gym, we have a machine which measures body composition. It's more accurate than using skinfold calipers or an online calculator, but it has a high enough error rate that results should be taken with a grain of salt. It's not like getting a DEXA scan. Some readers will be familiar with my rant about GPS watches. Most measurement tools available to consumers will not be terribly accurate. Outside of military, commercial, medical, and sporting use, even expensive measuring tools aren't always accurate. But that doesn't matter in this case. Generally speaking, while the numbers will vary, this machine tells everybody the same thing: lose bodyfat and gain muscle. Sure, it won't say that if you're an Olympic swimmer or a powerlifter. But for the average, untrained American, this will be the recommendation.
When they get this recommendation, most people want to know how they can improve their numbers. The answer is pretty simple: exercise every day, with a combination of strength training for all major muscle groups and aerobic exercise; eat a balanced diet. Many Americans want to know how much they should exercise. The best answer, applicable to the vast majority, is: more. A supermajority of Americans don't meet the minimum guideline set by the CDC of 150 minutes a week.
There are people who stay lean, seemingly no matter what they eat. The majority of them get more physical activity during their non-exercise time than most people do during their exercise time. They also eat less than most people think they do. They will claim they eat whatever they want and never exercise, and they perceive this to be the case, and yet their daily activity levels are quite high and their daily caloric intake is lower than they imagine.
People want to know how to eat healthier. Fewer processed foods. More vegetables (not “fruits and vegetables,” vegetables). More fiber. More protein. The majority of Americans do not meet the minimum RDA of fiber. While many Americans do meet the RDA of protein, this number is not a target amount, but a minimum number to support basic health and physical function. Most Americans could double or triple their protein intake without any adverse effect (as long as they keep the overall number of daily calories roughly the same). By eating more meat, fish, eggs, soy, and synthetic sources (protein powders, bars, etc.) and reading nutrition labels, while also eating less sugar and less dietary fat, it's quite reasonable for the average person to do this.
For example, if you substituted a boiled egg for your glass of orange juice, you would go from 0g of protein to 7g of protein, and from 150 calories to 70 calories. Keep doing this all day and you will quickly lower your caloric intake or keep it the same while increasing your protein intake.
Is there a maximum amount of exercise which is "too much?" Not really. If there is an amount which decreases longevity, very few individuals ever reach that amount. And there's some evidence to indicate that there isn't any diminishing return to VO2Max, no matter how high you go. An exceptionally high VO2Max can only be achieved with exceptionally high amounts (both volume and intensity) of cardiovascular exercise. When you stop training, your VO2Max decreases.
However, there is such a thing as too little recovery, or too much exercise too soon. Most injuries are the result of a combination of these. It is quite possible to overdo it if you're new to exercise, especially if you work a desk job and sleep less than 8 hours a night. Most athletes sleep 8-12 hours a night.
I read an article once (probably in Runner’s World) in which the author responded to a reader's question about the ideal racing weight. The reader was an American man in his forties. The author’s answer was that if the reader was a typical 45-year-old American man, the ideal racing weight was probably a good bit lower than he currently weighed. (Runners’ World might censor that response today, as it would be deemed insensitive.)
The majority of Americans could lose 10lbs (or a lot more) and their race times would improve. Some people think this answer is dangerous, because it encourages anorexia.1 I will pause to say that if anyone reading this has ever been diagnosed with an eating disorder, you can ignore this advice. However, the majority of Americans are overweight, and would improve their health by lowering their weight. Moreover, elite marathoners cut bodyfat down to 4% for men and 10% for women. This is the minimum amount of bodyfat needed for survival. They will also shed upper body muscle, any muscle which isn't propulsive or otherwise necessary for running. If you're not an elite athlete, this is dangerously low (they will intentionally gain bodyfat as soon as the race is over). However, they do this in order to run the fastest times in the world, and if you want to run the fastest times in the world, the ideal racing weight is as low as possible without injury or illness.