Nutrition with Donna Marlor
Smart nutrition can break the weight barrier Lately I've spotted thickened waistlines and drooping guts on biking century rides and tours. That's not a "big" problem if those carrying the extra weight aren't concerned about speed. But for the aspiring competitive racer, carrying an extra 15 pounds up a 13 percent grade
well, as one of my cycling friends put it, "You wouldn't want to carry your bike up a hill, would you?"
Losing weight is one of
the simplest ways to improve racing performance. Or, if you're into touring rather than racing, carrying less weight means spending less effort on climbs. The good news is dieting doesn't require tough interval workouts. No sweating. Just a quick muscle movement that involves zipping thy mouth shut.
While it's easy to say "just eat less," anyone who has tried knows that long-term weight loss is difficult. For an athlete there is the added challenge to lose body fat without losing
muscle, stamina, and most important, one's mental health. After all, what is life without chocolate?
Appetite regulation
I often hear statements like, "I felt like I needed to eat some fat" or "I craved a Whopper." Feeling depleted of energy and tired often results in food choices that are high in fat. Is that so bad?
Relying on feelings instead of science as a way to choose a good training diet can be risky business for an athlete trying to stay lean.
Take this
example: One three-hour, easy intensity Sunday ride costs a 170-pound biker about 1,400 calories. So why not a treat of great tasting, greasy, salty pizza? Well, one phone call and three pieces of a Domino's Meatzza pizza later you have racked up about 1,130 calories and an impressive 52 grams of fat. Not a problem. You're better than even, right?
But on Monday when you come home from work, it's a different story. Tired, hungry and mentally fatigued, there is that leftover Meatzza
staring you in the face, beckoning. Naturally, you eat it for dinner. Three more pieces. Problem is, today you didn't get out for a ride.
And what's more, you worked through lunch so hunger pangs were really hitting hard by 4 p.m. In lieu of passing out on the commute home, you polished off the last couple cookies in the break room. Yet that didn't seem to turn down the appetite thermometer.
Energy balance is not as finely tuned as we might like. Sure, eventually we feel
"full" and stop eating, but like the working bike dude in the example above, it's very easy to overdo it.
Findings from numerous studies blame two major players for encouraging over consumption of calories, namely: 1) palatability and 2) fat content. Add "easy accessibility" and now you have a formula for weight gain. Although the body does have a feedback mechanism that eventually tells the brain "enough," it takes about 30 minutes to kick in. How long does it take to eat half a
pizza? Less than 10 minutes.
Metabolic changes with dieting
Last month, one of my male acquaintances chided me for not knowing who was in the Final Four of the collegiate basketball playoffs. I responded to his question with one of my own: "Who was Ansel Keys?" He surprised me in an e-mail: "Wasn't he the guy responsible for WWII K rations and the original South Beach Diet?" He's a smart guy and this was a typical smartie pants answer from him.
For those of you who still
haven't a clue, here is a quick nutrition history lesson a very important lesson if you're interested in losing some.
Ansel Keys was the nutrition scientist responsible for masterminding one of the most innovative studies on the effects on human starvation ever conducted. He and a group of talented associates carried out a careful physiological and psychological study of initially healthy conscientious objectors to World War II through six months of semi-starvation (about a 50
percent calorie deficit), followed by a year of rehabilitation (refeeding).
The study took place at the University of Minnesota, and the data it produced is invaluable as this type of research would not have a chance of being approved by today's ethics review boards. Although the original study results were published in 1950, the lessons on metabolic changes that occur during weight loss still apply.
Keys' subjects were not the morbidly obese subjects of today's weight-loss
studies, but were more like one of us: active, close to normal weight, or maybe a few pounds overweight. Here are some important lessons from the Minnesota study that all endurance athletes should consider when attempting to lose weight.
LESSON 1: There is an energy cost to metabolizing food, and a reduction in food intake will reduce the body's metabolic rate by 5 percent to 10 percent. In other words, less food in means less work for the body to convert food energy into a usable form
of energy for staying alive. In other words, if you eat less, you burn less. Skipped meals and drastic calorie cuts are not the way to go about losing weight.
LESSON 2: There is a reduction in one's metabolic rate that occurs relatively quickly as the body responds to starvation stress to spare both lean and fat tissue. This reduction in metabolic rate is more pronounced for lean individuals than obese; it is the body's survival mechanism. Scientists refer to this as "nonspecific
thermogenesis." But there's more.
LESSON 3: A secondary defense system of the body against starvation has a much slower onset, but the effect on metabolism is again a reduction. This defense system is largely regulated by the degree of fat depletion.
As fat loss takes place due to a caloric deficit, there is a further reduction in metabolic rate. Interestingly, the more obese a person is, the less the suppression in thermogenesis for the same degree of body fat depletion. In other
words, a slightly overweight individual who loses 3 pounds of body fat will experience a greater reduction in metabolic rate (calorie requirements) than an obese person who loses 3 pounds of body fat.
What's the bottom line for an athlete who is looking for a 5- to 10-pound weight loss? Go slow. Drastic cuts in calorie intake will markedly reduce metabolic rate, and, as body fat is reduced, further cuts in metabolic rate will occur.
The rebound phenomenon
One of the last
pearls of diet wisdom that Key's studies demonstrated was what happened when an individual quit starving (stopped dieting) and started to increase calorie intake again. It seems our bodies are much more efficient at restoring fat tissue than lost muscle, which also is lost with an overall decrease in body weight.
One of the psychological consequences to large reductions in energy intake is marked overeating that occurs when food is available. Unfortunately, the end result is an
increase in body fat greater than what was originally present.
Practical weight loss tips
Differences in genetics, training regimens and food preferences make it hard to recommend a single diet solution for weight loss in athletes. If you've tried to lose weight and have been unsuccessful, then doing "more of the same" may not be the right approach.
What follows are some suggestions to help you achieve your weight goals and performance goals.
Know how many calories
you need to maintain your weight at a low activity level or period of rest. You should not go below that amount by more than 500 calories.
Remember the law of averages. There are seven days in a week. If you decrease your calorie intake Monday through Friday but splurge on the weekend, the extra gets added back in enough to offset any diet.
Focus on making healthy food choices, avoiding the obvious: high-fat, high-sugar and deep-fried foods. Select foods with low caloric density,
such as fruit, vegetables and broth-based soups.
Keep track of what you eat in a daily log. Consistent self-monitoring over a period of time will help you to see how physical activity, fatigue and emotional state affect your food choices.
Time your intake of carbohydrates. For exercise of greater than an hour's duration, plan to take in 30 grams of carbohydrates. This will help to maintain stamina for a workout and increase your overall calorie output.
Consume a recovery snack
following a workout over 90 minutes in length. Quick repletion of glycogen stores and blood sugar is best done with a light snack of carbohydrate and protein. Not sure what to eat? Aim for about 200 calories: cereal and low-fat milk, a peanut butter sandwich or a Clif Bar recovery drink are examples.
Have regular meal times and try to eat on your own schedule. Eating early, especially for the evening meal, often does not fit in well with social occasions. If going out for dinner,
mentally divide your entrιe into thirds: Eat one-third of your calories as a snack before you leave, and have two thirds for dinner. Skip dessert and that second cocktail.
Sometimes, despite your best efforts, successful weight loss remains elusive. To find a qualified health professional who can assist you, check out www.eatright .org, the website of the American Dietetic Association.
Donna Marlor MA, BSN, RD holds a bachelor's of science degree in nutrition and nursing from
Northern Michigan University and a master's degree in educational psychology from the University of Minnesota-Duluth. She is a former NMU cross-country ski team member and still competes in skiing and running events at the master's level. Marlor resides in Marquette, Michigan, with her husband and chocolate Lab. She can be reached at www.DonnaMarlor.com.
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