If you’ve been reading this newsletter for any length of time, you’ll know that I’m a big fan of any workout routine that combines cardiovascular (e.g. cycling, walking or sprinting) and resistance exercise (e.g. weight-training).

In fact, I’ve talked about this subject so often that I’m worried you’re getting annoyed at me right now for bringing it up again. That’s why the headline about cardio and weights not being the best way to lose fat might have come as a surprise.

Part of the reason I wrote it was to get your attention. But I also wanted to emphasize the fact that exercise is only one piece of the puzzle when it comes to burning fat and building muscle.

Before I explain exactly what I mean, here are two examples to illustrate my point.

STUDY #1: In this study, conducted at Penn State University, a group of women took part in a 12-week program of diet and exercise [2]. The women were assigned to one of four groups:

• The first group served as a control group, and did nothing.

• Group two followed a low-fat, high-carbohydrate diet.

• Group three combined the same diet with regular aerobic exercise.

• The fourth group also followed the same diet, but added aerobic and resistance exercise (weight training).

As you might imagine, all three groups lost weight.

• The diet-only group lost 13.6 pounds.

• The diet plus aerobic exercise group lost 15 pounds.

• The women combining diet with resistance and aerobic exercise lost 15.4 pounds.

However, the loss of fat was greatest in the women who combined a low-calorie diet with aerobic exercise.

In fact, the women who trained with weights actually lost 3.7 pounds of muscle.

STUDY #2: The trial, published in the Journal of Applied Physiology, tracked a group of 31 women during a six-month exercise program [1].

At the beginning and end of the study, body fat levels were measured using a sophisticated technique called dual-energy x-ray absorptiometry (DEXA for short).

The program consisted of 90 minutes of exercise (weight-training, running and military drills) five days each week.

Despite the fact that the women exercised for more than seven hours each week for six months, they lost only 5.7 pounds of fat. That’s just 0.2 pounds per week.

What do both of these studies have in common?

None of the women in either trial were following a decent diet.

In study one, total calorie intake was too low (7 calories per pound of body weight). What’s more, 70% of those calories came from carbohydrate, leaving just 15% for fat and 15% for protein. It’s no surprise they lost so much muscle.

In study two, the women were not told to change their diet, and could eat what they wanted.

The bottom line

If you want to lose stubborn fat, then exercise alone — be it weight-training, cycling, Pilates, or the so-called “core-stability” workouts that seem so popular at the moment — won’t be enough. You’ll need to eat right too. If you want to make this the year when you finally get the body you want, now’s the time to take a closer look at your diet.

For more information, see How to burn fat without losing muscle in the Members-Only Area. Alternatively, download a copy of Tom Venuto’s excellent book Burn The Fat Feed The Muscle. There’s some great information in there about what and when to eat, as well as easy-to-follow fat-burning exercise programs that work.

Your basal metabolic rate - the number of calories your body burns each day just to stay alive - tends to drop as you age.

According to conventional wisdom, this is because you lose a small amount of muscle each year.

However, many people don’t realize that muscle mass is not the only thing that affects your basal metabolic rate.

In fact, studies show that your metabolic rate declines with age independently of muscle loss. In other words, young physically active men tend to have a higher metabolic rate than their older counterparts, even if they have the same amount of muscle.

Why?

The age-related decline in metabolic rate - even when muscle mass is taken into account - is because of two reasons.

• Firstly, there’s a strong link between exercise volume and your metabolic rate. In other words, the more exercise you do, the higher your metabolic rate. The fact that people tend to exercise less as they age is partly responsible for the drop in metabolic rate.

• Second, metabolic rate is also linked to total calorie intake. This means that the more you eat, the higher your metabolic rate. A reduced metabolic rate in older physically active men could be due to the fact they eat less than their younger counterparts.

Some evidence for this comes from a research group based at the University of Colorado [1]. They compared a group of young and older inactive men with physically active men of a similar age.

Even when differences in muscle mass between young and old subjects were taken into account, basal metabolic rate was lower with age in both the inactive and physically active subjects. The older men burned around 64-68 calories per hour, compared to 72-77 calories per hour in the younger subjects.

However, when researchers compared older and younger subjects doing the same amount of exercise and/or eating the same number of calories, there was no difference in basal metabolic rate.

The same holds true in women as well as men. Research comparing premenopausal and postmenopausal women shows that basal metabolic rate, again adjusted for age-related muscle loss, was roughly 10% lower in postmenopausal women who do no exercise [2].

But there was no difference in metabolic rate between premenopausal and postmenopausal women who exercise regularly.

Energy flux

The link between adjusted basal metabolic rate, exercise volume, and energy intake involves a concept known as energy flux, which refers to the flow of calories (or energy) through your body.

A high energy flux means that you’re eating a large number of calories, but balancing that with an equally high volume of exercise. A good example of someone with a high energy flux would be a cyclist taking part in the Tour de France.

Despite the fact these athletes eat thousands of calories each day, they’re so lean simply because they do so much exercise.

Someone following an extremely low-calorie diet while doing little or no exercise is a perfect example of low energy flux.

A lot of people use this approach to lose weight. And it does work, if only for a short time. If you cut your calorie intake too much for long, several things will happen.

• You’ll end up losing muscle as well as fat. Half of the weight lost on a very low-calorie diet comes from muscle.

• You won’t have the energy to exercise. The result is that your metabolic rate will slow down, and weight loss will get harder.

The bottom line

The bottom line is that a drop in your metabolic rate is not an inevitable consequence of aging, and has a lot more to do with the way you live your life.

You can minimize the age-related drop in metabolic rate by maintaining a high energy flux - balancing a nutrient-dense diet with regular exercise.

Not only will this help you stay lean, it’s a great way to provide your body with more of the vitamins, minerals and other nutrients it needs to stay healthy

(Note: If you’ve been putting off starting an exercise program because you think you’re too old or just too far gone, grab a copy of Fit Over 40: Role Models For Excellence At Any Age. You’ll find more than 50 inspiring real life success stories which prove that you can boost your metabolism, gain muscle and lose all the weight you want regardless of how old or out of shape you are!)