Building muscle is a goal that many people share. Achieving that goal requires a lot of work. Everyone has a maximum genetic potential for muscle growth that diminishes with age (called sarcopenia). This decline in muscle mass can lead to frailty, reduced mobility, and increased risk of injury. Fortunately, resistance training and dietary protein can help to restore this sensitivity.
Protein
Protein is a very important nutrient that helps muscle building. It also provides the amino acids that are used to repair muscles after a workout. Protein synthesis is stimulated by strength training exercises, but it is also stimulated by eating protein-rich foods. A high-protein diet can help to stimulate MPS and therefore contribute to the growth of muscle tissue. Protein quality is important, too. Some experts recommend eating a combination of animal and plant proteins to ensure that you get all of the essential amino acids. Some plant proteins are harder to digest, however, and have varying amino acid profiles.
Muscle protein synthesis is impaired with aging, and this may partly explain the loss of muscle function associated with sarcopenia. Increasing habitual physical activity may be a way to improve the anabolic response to protein intake in older adults. However, this has not yet been shown to reverse the age-related deterioration in muscle protein synthesis.
Carbohydrates
Carbohydrates are an important nutrient for muscle growth because they create glycogen that is needed to power resistance training. Carbohydrates also increase protein synthesis and decrease protein breakdown. The type of carbohydrate is important, as are the timing and amounts. Simple carbohydrates are made of one or two sugars, such as fructose (fruit) and lactose (dairy). Complex carbohydrates contain a group of sugars that is broken down into glucose slowly and provides energy over a longer period of time. These include fruits, vegetables, grains, and legumes.
Generally speaking, carbohydrates should be the largest source of calories for bodybuilders. However, it’s important to consume healthy carbs like whole foods and avoid refined sugars when possible. It’s also recommended that you consume carbs before and after training to fuel your workouts and replenish glycogen stores. This helps prevent muscle breakdown and allows you to store more carbs as muscle instead of fat.
Fats
Fats supply energy and are also important for cellular function. A gram of fat contains 9 calories, twice that of protein or carbohydrates. A healthy diet should be balanced with protein, carbohydrates, and fats, as all are needed for optimal health. Muscle-building requires adequate nutrition and training. But that doesn’t mean you need to eat more than you burn. Too many calories, whether from unhealthy, high-fat foods or even from a well-balanced diet, will get stored as body fat.
The good news is that resistance training can help reduce the loss of muscle mass that occurs with aging. In this video clip, Dr. Stuart Phillips explains how physical activity makes muscles more sensitive to protein or amino acid ingestion, and how this can offset the natural anabolic resistance that occurs in elderly people. He recommends two to three meals and snacks containing both protein and carbohydrates for the best results. The best protein sources include fish, lean meat, eggs, tofu, beans and pulses, and low-fat dairy products.
Vitamins
While hitting the gym and pumping iron are important for muscle growth, there is more to building muscles than just going crazy in the weight room. It also requires the right diet and supplementation to make gains. The key to gaining muscle is creating a positive protein balance between muscle protein synthesis and breakdown rates. This is accomplished by consuming protein-rich foods, resistance training and exercise, and amino acid supplementation. Unfortunately, as people age, they become less responsive to these anabolic stimuli, leading to decreased skeletal muscle mass and reduced physical function over time.
It is thought that this decrease in anabolic sensitivity in the aging population is due to a combination of hormonal changes and a reduction in processes related to inflammation. Fortunately, a lifestyle approach to healthful eating and prebiotic/probiotic/symbiotic supplementation may mitigate anabolic resistance by increasing the production of SCFA in the gut microbiome. This may in turn promote muscle protein synthesis and reduce muscle protein breakdown in the aging population.
Conclusion
In healthy older people, there is a blunted stimulation of muscle protein synthesis rates to common anabolic stimuli such as ingestion of dietary protein and resistance exercise. This phenomenon is known as anabolic resistance. The primary cause of this is desensitization to the normal anabolic response to protein ingestion, and this can be overcome by restoring the basal-fasted rate of MPS.
