Eat to Turn Up the Heat

Jerry Brainum

When to eat for maximum fat burning during exercise

Many studies show that eating foods that are rapidly used energy sources, such as carbohydrates, just before a workout blunts the use of fat as a fuel. Carbohydrate drinks do, however, offer a few notable advantages when drunk during the workout. Drinks that contain the proper level of carbs (8 percent or less) combined with some electrolytes (minerals) to speed fluid uptake provide hydration even more efficiently than plain water. Carb drinks maintain energy levels during workouts that exceed an hour and blunt the rise in cortisol that would normally occur after an hour of hard training. But it’s all at the expense of fat burning.

I’ve seen people eat full meals immediately before or even during workouts. Such meals will have a delayed digestion, as blood is shunted from the gastrointestinal area to the working muscles, so the food goes more or less undigested until the workout ends. In addition, weight training is powered mainly by stored muscle glycogen, which is a reflection of what you ate 24 to 48 hours earlier. The only benefit derived from eating just before or during a workout is psychological.

But what’s the time interval after a meal if you want to burn the most fat during a workout? A new study, involving obese women over age 50, examined the issue.1 That group may seem to have little relevance for a younger population, but the principles governing the study apply to anyone, regardless of age.

The women ate meals either one or three hours before exercise. Not only did exercising three hours after a meal result in greater fat oxidation, but the level of fat burning was also similar to what happens after fasting. The three-hour interval led to lower heart rates during exercise and lower glucose, lactate and insulin levels, all of which favor fat burning.

Why did eating a meal one hour before exercise lead to less fat burning? The authors explain that eating so close to a workout increases the carbohydrate content of the blood, resulting in a blunted fat-burning effect. The meal produces higher levels of lactate, which blunts fat burning during exercise. Elevated insulin levels after a meal also block fat release and oxidation during exercise.

The lowered heart rate occurred because of the heart’s role in supplying blood for digestion purposes the first hours after a meal. By the three-hour point the meal was digested, leading to less stress on the heart during exercise.

Even though the study featured obese older women, the relationship between fat use and exercise applies to anyone, regardless of sex or age. In effect, the longer you wait between your last meal and your workout, the greater the level of bodyfat you’ll burn during the workout.


1 Dumortier, M., et al. (2005). Substrate oxidation during exercise: impact of time interval from the last meal in obese women. Int J Obesity. In press.


Train Around Low-Back Pain

Joseph M. Horrigan

Train Around Low-Back Pain

One in three Americans experiences lower-back pain, and trainees are no exception. Some have made unwise exercise selections that contributed to their problem; others simply developed lower-back pain, and they happen to train too. The problem is how you should train around the pain.

Trainees with 10 or more years of consistent training often find they must give up some exercises. Time after time they say, “I had to give up bent-over rows because of my lower-back pain,” “I had to stop squats because of lower-back pain [or knee pain],” or, “I had to give up bench presses [or overhead presses] due to shoulder pain.”

How to Refresh Your Instinctive Workout

Larry Scott

How to Refresh Your Instinctive Workout

We human beings seem to be slow at absorbing new ideas—especially if the new idea is directly in front of us. As Irish poet Aubrey T. de Vere said, “Prejudice, which sees what it pleases, cannot see what is plain.”

We’ve all heard of instinctive training, or I.T. Many consider it the most effective method of training, at least for advanced bodybuilders. It can generally be described as a system in which the trainee tries to intuitively discover the unique combination of exercises that will be most effective for his body. I.T. recognizes that each trainee is unique and therefore that the system of exercises just right for him may not be right for the next fellow.

Fat-Burning Firestorm Ephedra-Free Fat Burners

George L. Redmon

Fat-Burning Firestorm Ephedra-Free Fat Burners

Unless you’ve been keeping company with Rip Van Winkle, you’ve probably seen many negative reports concerning ephedra over the past year or so. Despite its long history of safe use, the herb has been increasingly subject to reports of adverse reactions. Touted for its ability to reduce lipogenesis (the formation of fat) and induce thermogenesis (heat that breaks down fat cells), as well as treat asthma and upper-respiratory complications, ephedra has been linked to reported cases of stroke and heart attacks. Researchers at the U.S. Food and Drug Administration have speculated that ephedra, coupled with other stimulative products, is behind those reactions. Even without 100 percent certainty, many supplement manufacturers stopped using ephedra in their products, even before the FDA ban went into effect. That initiated interest in alternative products that can induce fat burning without raising blood pressure or triggering other risk factors. So here’s a review of the best-known natural fat burners that can be used safely and effectively.

T Factor: Testing Tribulus

Jose Antonio, Ph.D.

T Factor: Testing Tribulus

Tribulus terrestris, also called puncture vine, is credited with an array of virtues. Some claim it improves sexual function in humans. In Turkey it’s commonly used for blood pressure and cholesterol treatment. In China and India it’s been used to treat liver, kidney, urinary and cardiovascular problems; of course, the Chinese and Indians have been using ingredients for centuries that Americans have only recently begun to examine. But what does science have to say about this herb?

Catabolic Cardio Combat

Ron Harris

Catabolic Cardio Combat

I’ve often written about the catabolic effects cardio can have on muscle mass and suggested limiting cardio during specific periods, such as the so-called bodybuilding off-season, when you’re trying to gain strength. But what about when you’re trying to get ripped? Most of us find it necessary to do cardio on a regular basis and for substantial amounts of time to experience the fat-loss results we want during a cutting or precontest phase. The trick is to know how much is too much and when to do less in terms of frequency and volume.