Ima coffee/caffine junkie....
The Caffeinated Runner
How can caffeine help your performance? By Matt Fitzgerald For Active.com
A number of studies have shown significant performance increases in various endurance disciplines, including running, following caffeine ingestion. In one study, elite runners improved their time in a treadmill run to exhaustion by 1.9 percent with caffeine. Caffeine boosted time to exhaustion in a cycling test by 15 minutes in another study. And in a study involving swimmers, caffeine was found to enhance performance in maximal-effort swims of up to 25 minutes' duration.
How does the world's most widely used drug achieve these effects? It appears caffeine enhances performance in shorter events by stimulating the nervous system in ways that enable the muscles to contract faster and more efficiently. In longer events, caffeine delays fatigue by reducing the athlete's perception of effort. Specifically, it increases the concentration of hormone-like substances in the brain called ß-endorphins during exercise. The endorphins affect mood state, reduce perception of pain, and create a sense of well-being.
Caffeine has also been found to delay fatigue during exercise by increasing the level of free fatty acids in the bloodstream and thereby boosting fat burning and conserving muscle glycogen (which is the limiting fuel source for muscle work). This latter effect of caffeine used to be considered the major mechanism by which it enhanced endurance performance, but it is now known to be a minor factor. In fact, for those who normally maintain a high-carbohydrate diet, it is virtually a non-factor.
Caffeine is a diuretic, meaning that it increases urine production, which could theoretically exacerbate dehydration during exercise. However, exercise negates this effect. In a recent scientific review, researchers from the
When and How
Runners commonly take caffeine in pill form (proven to be more effective than equal amounts of caffeine consumed in coffee) 30 to 60 minutes before races to enhance competitive performance. What's the optimal amount? The ergogenic effect of caffeine is dose-dependent. The maximum effect is seen with doses of five to six milligrams per kilogram of body weight. For a 150-lb runner this translates to roughly 340-400 mg, or the amount of caffeine you'd get in 14 to 17 ounces of drip brewed coffee. The minimum amount of caffeine the average runner must consume for a measurable ergogenic effect is about two mg per kilogram of body weight.
It makes less sense to use caffeine as a daily workout performance enhancer, for two reasons. First, workouts are seldom maximal efforts, and the rationale for caffeine supplementation is to enhance maximal performance. Second, the ergogenic effects of caffeine consumption decrease with habituation. For this reason, if you are a regular coffee drinker, you should cease coffee consumption four to six days before participating in a race.
Caffeine and Health
In moderation, caffeine consumption does not cause any health problems. In fact, a daily cup of joe is good for you. The health benefits of coffee come from its caffeine content and its unique blend of antioxidants. According to
However, heavy caffeine use can cause or exacerbate problems ranging from headache to insomnia, and it is possible to become physically dependent on the drug. Caffeine is especially harmful when used as a means to stimulate artificial wakefulness or energy in those suffering from conditions such as chronic fatigue. So if you do like caffeine, limit yourself to one mug of coffee or green tea in the morning. Those *****ly on regular "caffeine injections" throughout the day are well advised to cut back.
Caffeine and Sports Drinks
A new alternative to taking a single large dose of caffeine prior to racing is to consume a caffeinated sports drink throughout races. In a recent study, conducted at the
They found that the rate of exogenous carbohydrate oxidation was 26 percent higher in the cyclists receiving carbs with caffeine than in those receiving carbs without caffeine. The study's authors concluded that caffeine may have increased the rate of glucose absorption in the intestine, providing fuel to the working muscles more quickly. The likely effect on performance is the ability to work harder for a longer period of time without becoming fatigued.
Another recent study looked at the effects of consuming a caffeinated sports drink on performance in a warm environment. Sixteen highly trained cyclists completed three trials. Subjects cycled for 135 minutes, alternating between 60 percent and 75 percent VO2max every 15 minutes for the first 120 minutes, followed by a 15-minute performance ride. In one trial they consumed flavored water; in another, a conventional carbohydrate sports drink; and in another, a caffeinated sports drink.
The cyclists completed 15 percent to 23 percent more work during the caffeine trial than in the other two trials. Ratings of perceived exertion were lower with the caffeinated sports drink than with the placebo and the conventional sports drink. After cycling, maximal strength loss was found to be two-thirds less for the caffeinated drink than for the other beverages.
This new research suggests that using a caffeinated sports drink may be the best way to go in races.
Have You Misplaced Your Focus? by Jeremy Gentles, BS, CSCS
Exercise is no good for weight loss! Well, not exactly. While there are a number of benefits associated with bariatric surgery independent of weight loss, such as relief from Type II diabetes, loss of excess body weight remains the primary benefit of weight loss surgery. Unfortunately, for many individuals, weight loss is also considered to be the primary benefit of exercise. Why is this unfortunate, you ask? If exercise does significantly contribute to weight loss after bariatric surgery, great; but if it does not, and your focus remains losing weight through exercise, this goal may easily become a barrier to success.
Exercise Is No Good for Weight Loss?
There is a limited amount of research assessing the impact of exercise on total weight loss after bariatric surgery. However, the data that does exist is similar to what has been seen in individuals on clinically guided low-calorie or very-low-calorie diets. This is reasonable, as bariatric surgery includes anatomical adjustments to help control caloric intake versus the behavior modification and clinical supervision used in clinically guided nutrition and exercise programs. A 2005 study in the journal Obesity Surgery looked at 100 duodenal switch patients preoperatively through 18 months post-operatively. The group was divided into exercise and non-exercise groups: the exercise group reported participating in exercise at least three times a week for no less than 30 minutes per session during the first six months after surgery, while the non-exercise group reported less or no exercise.
Eighteen months after the duodenal switch, both groups had lost very similar amounts of total body weight. Yes, that’s right: those who did not exercise lost the same amount of weight as those who did. There was one key difference, of course! The exercise group had significantly higher levels of muscle tissue at the end of the study than those who did not exercise. This means that they also had lower body fat percentages and were stronger, more functional and more prepared for long-term weight-loss maintenance. Did these differences show up on the scale? Of course not, and neither will yours. You must be able to look deeper than the scale. While exercise may not increase the total amount of weight loss during periods of significant caloric restriction, including after bariatric surgery, exercise is consistently a habit of those who achieve long-term success. Regular physical activity is a key component of maintaining weight loss, with or without bariatric surgery. Notice the word “maintaining”—this is extremely important. Exercise will help maintain the weight loss you have achieved through WLS, but most likely will not cause extensive weight loss itself.
“Big deal!” you might say. “Isn’t this trivial?” Absolutely not. Let me explain. Imagine being several months post-op WLS. You are satisfied with the amount of consistent weight loss you are achieving, but you feel you can do better, especially if you start exercising more regularly. You begin an exercise program, but several weeks into the program, your rate of weight loss has not significantly increased. For many obese individuals, this scenario is just another in a long list of failed attempts at exercise. Each time you fail, it makes successful long-term participation in an exercise program more difficult to attain. What’s the problem? Is it that exercise does not dramatically increase weight loss after bariatric surgery, or is it the expectations we place upon exercise itself? You must set yourself up for success, not failure. So where do you focus?
A Healthy Focus
No matter how ingrained it is in our heads that exercise causes weight loss, this is not always the case. However, the numerous benefits of exercise are often independent of weight loss. In other words, even if you never lose another pound in your life, exercise will enhance your health. With weight loss off your mind (right?), you can focus on the other benefits of exercise. Without a doubt, exercise can help you become more functional, control your blood sugar, lower your cholesterol levels, and decrease your blood pressure. Moreover, the greatest decrease in disease ris****urs with moderate levels of physical activity. You don’t need to be able to run 10 miles to see real results. If you regularly mow your lawn (not riding), work in the garden, or walk for 30 minutes, you are well on your way to reaching the most important goal—health! The power of exercise is not demonstrated on the scale, but in the way we feel. When it comes to exercise, a healthy focus is best.
Jeremy Gentles, BS, CSCS is ObesityHelp’s staff health and fitness expert. Jeremy studied Exercise Science at
