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As a woman who has been running for (gasp!) three decades, and who plans to continue for the next three decades and beyond, I often think about the keys to longevity in running. And as a sports dietitian, I am constantly looking for nutrition angles. Combining those two, I land on the importance of building and maintaining muscle, which means both taking in adequate protein and doing resistance-training exercise.
Quick Science Review
Amino acids are the building blocks of protein, and they’re used to fuel our workouts and for muscle protein synthesis. When we work out, we break down muscle fibers, then need to consume protein and rest our muscles in order for them to repair and strengthen. Thankfully, with adequate protein and total calorie intake in tandem with continued training, decreases in muscle mass and a decline in your resting metabolic rate (RMR) are not inevitable.
Protein needs vary by age, gender and activity level. According to the Academy of Nutrition and Dietetics and American College of Sports Medicine, athletes should aim for 1.2 to 2.0 grams of protein per kilogram of body weight per day (which is 60 to 100 percent of the recommended daily allowance for non-athletes).
- Female endurance athletes generally need 1.2 to 1.4 grams per kilogram per day.
- Athletes also engaging in resistance training may require 1.6 to 1.7 grams per kilogram per day.
- Anyone 52 to 75 years old shows better protein synthesis when intake is 1.5 grams per kilogram.
This amounts to 65 to 92 grams per day for a 120-pound woman and 82 to 115 grams per day for a 150-pound woman.
Distribution of this protein intake is key—it should be spread out evenly throughout the day, with 15 to 20 grams immediately following exercise and a total of three to four times each day. Examples of 15 to 20 grams of protein include:
- 3 oz. lean meat
- 2 to 3 large eggs
- 6 to 8 oz. Greek yogurt
- ½ to ¾ cup cottage cheese
- ¾ to 1 cup tofu
- ½ cup beans
Carbohydrates need to be consumed along with protein (and in adequate amounts overall) to ensure that protein goes toward muscle repair and building and does not need to be oxidized for fuel/energy. It is important to note that epidemiological studies estimate that up to 50 to 60 percent of female endurance athletes do not meet their total energy intake needs on a regular basis, putting them at higher risk for protein deficiency and increased total protein needs. To maintain muscle mass and RMR throughout the years, we must consume adequate total calories and carbs, not just adequate protein.
Finally, to ensure we cover all bases, all women, but especially pre-menopausal women, need to ensure adequate iron intake to support protein and enzyme function as well as oxygen saturation and transport, which directly correlates to endurance performance. Adequate calcium and vitamin D intake are critical to bone health and therefore longevity in sport and running through the years. Adequate total fat intake, specifically high-omega-3 foods (salmon, mackerel, walnuts, chia, flax, cod liver oil) help to decrease inflammation, prevent injury and keep us running healthy and strong.
So if you, like me, want to continue running for years to come, ensure you meet your total protein and total calorie needs, and take in adequate total fat, iron, calcium and vitamin D. If you’d like to get a better assessment of your nutrition needs, I recommend seeking the advice of a board-certified sports dietitian who conducts RMR testing to ensure you are on track to run for life!
Lauren Antonucci is a registered dietitian, board-certified sports dietitian, marathoner and triathlete. She is also the owner/director of Nutrition Energy in New York City.