The Grams of Protein, Fat & Carbs for Lean Muscle

Calorie Requirements

Exercise is mandatory when it comes to getting lean, and your calorie needs reflect your activity level. Most active women need about 2,000 to 2,400 calories a day to maintain a healthy weight, according to the Dietary Guidelines for Americans 2010. However, active women who want to shed extra pounds will benefit from reducing their calorie intake to 1,200 to 1,600 calories a day, according to the National Heart, Lung and Blood Institute.

Protein Needs

Protein is your key to success when it comes to building or maintaining lean muscle mass to tone up your body. Although the Institute of Medicine suggests adults need 10 to 35 percent of their energy intake from protein, a review published in a 2009 edition of “Nutrition and Metabolism” reported that protein needs are based on your body weight, not your energy intake. The International Society of Sports Nutrition holds that when you work out regularly -- which is required to maintain lean muscle -- you benefit from eating 0.64 to 0.91 gram of protein per pound of your body weight per day. Therefore, a 125-pound woman should aim for 80 to 114 grams of protein each day.

Carb Recommendations

Since carbs are your body’s main source of energy, especially during workouts, you need more carbs than protein or fat. A review published in a 2012 edition of the “Journal of the International Society of Sports Nutrition” reported that female bodybuilders consume about 54 percent of their daily calories from carbs, or about 297 grams of carbs per day for a 2,200-calorie diet. For women who want to drop weight and fat, eating fewer carbs can help. A study published in a 2012 edition of the journal “Nutrition” reported that reducing your carb intake will help lower your calorie intake for weight loss. However, be sure to get at least the recommended dietary allowance for carbs -- which is 130 grams per day – to prevent negative side effects, like difficulty concentrating, headaches, nausea, dizziness and fatigue.

Dietary Fat

Fat is a must in your diet, but since it provides 9 calories per gram – carbs and protein only contain 4 calories per gram – eating too much fat is detrimental to obtaining that lean, defined look. The Institute of Medicine suggests you eat 20 to 35 percent of your calories from fat. However, to avoid excess body fat and stay lean, shoot for about 25 percent of your calories from fat, which is equivalent to 61 grams of fat per day for a 2,200-calorie diet.