Avoiding Mistakes When Building Muscle and Losing Fat

Women lifting weights
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Building muscle and losing fat are the twin goals of weight training and physical conditioning, but the body resists doing both at the same time. They are contradictory physiological processes. Your body has evolved to increase both fat and muscle in times of plenty and to lose both muscle and fat in times of scarcity when food availability is low.

How can you hold increased muscle while shedding loads of fat to get a nice-looking body with six-pack abs? Start with not falling for these 10 common mistakes of diet and exercise that will inhibit losing fat while gaining muscle.

Eating Too Little

You can't pack on muscle if you don't create an anabolic environment, which means you must eat enough to maintain sufficient body weight and energy to fuel exercise. You don't need to eat huge amounts of protein or calories, but you need enough to keep your body going.

Eating Too Much

Many people underestimate how much they eat, as shown in calorimetric scientific tests. Very low-calorie diets are not necessary, but you do have to count calories at some level to cut your total energy intake to lose fat.

Fueling Haphazardly

When your body is fuel-hungry, either during intense exercise or when your metabolism has been revved up for the few hours after you exercise and you have not eaten, unless you give it some fuel, your muscle may be broken apart into glucose by the hormone cortisol.

The trick is to provide just enough carbohydrates to prevent cortisol from performing this negative task, but not so much to cause your body to slip into positive energy balance (eating too many calories to support fat loss).

A piece of toast and honey or a small sports drink before exercise should provide the right amount of fuel.

Refined Carbohydrates

Carbohydrates are not your enemy, but you do have to restrict the consumption of foods that are enticing and easy to overeat and have a less-than-ideal effect on your waistline. Biscuits, cakes, muffins, candies, puddings, potato chips and crisps, crackers, sugary drinks, etc—these items need to be curtailed substantially.

Excess Fat Intake

Nutritionally, you may know about good fats and bad fats, but to lose weight (fat weight), getting your fat intake between 20% and 30% is a useful approach. Fat has 9 calories per gram compared to 4 calories per gram for carbohydrates and proteins, and it doesn't matter what fat it is. This makes it much easier to overeat when you're consuming foods with fat.

Not Eating Enough Protein

You don't have to go crazy about this and consume protein drinks day in and day out, but replacing some of those refined carbohydrates and fat with a modest increase in protein should help maintain or enhance your muscle while you're losing fat. Don't make it all animal protein, though: Dairy and plant-based proteins (such as whey, soy, and pea proteins) are good options. And you still need to exercise those muscles.

Insufficient Weight Training

As you lose fat, the only way to protect that muscle and bone from going down with it is to place stimulatory stress on that muscle and bone. That means relatively intense weight training workouts at least three days each week.

Insufficient Intensity

Although lifting light weights with higher repetitions will encourage muscle growth, you are much more likely to see results if you lift heavy. Ideally, this should be at least around 65% of your maximum lift possible.

If you can squat 130 pounds (60 kilograms) maximum, then you should look at training with 85 pounds (38 kilos). If you don't or cannot measure your maximums, then make sure the final repetition in any set is hard to complete.

Eight to 12 repetitions and three to four sets for each exercise is a good basic program.

Skipping Cardio

Aerobic exercise helps you burn off those calories. Steady-state cardio at a moderate pace, or short bursts of high-intensity cardio intervals—in conjunction with a good weight training program—will get you in a good place for fat loss. If you do cardio for longer than about an hour you risk breaking down muscle for fuel, and you need to hang onto as much muscle as you can in this scenario.

Skimping on Precision

This may seem obvious, but what you are attempting to achieve is not trivial. For most people who have achieved their weight loss goals, the net loss includes fat and muscle and often some bone as well. This is the result of catabolism, the breaking down of body tissue that defines weight loss.

To achieve muscle maintenance (or enhancement) and fat loss goals, you have to have a clearly documented program, and you have to apply it with precision. That means taking the time to apply each step accurately, logging those steps in a diary, and recording energy inputs and outputs in the form of food and physical activity.

A Word From Verywell

One last point concerns overtraining. Don't be afraid to take a week off or reduce your training by 50% for one week if you feel your body is not coping with the volume and intensity. Cycling volume and rest may even be important for healthy muscle growth. Go to it.

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