A study at the Institute for Research in Biomedicine (IRB Barcelona) has discovered that the protein Mitofusin 2 protein could serve as a therapeutic target to ameliorate sarcopenia in the elderly.

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Sarcopenia, the loss of skeletal muscle mass and strength, is a major problem as people age. It can lead to disability, osteoporosis, falls, hospital stays, and even death._[1] Wondering how to prevent sarcopenia? Taking a few natural steps now can improve muscle health and help maintain autonomy and well-being into old age.

How to Prevent Sarcopenia: Start with an Understanding of Causes

Two of the most preventable and treatable factors that contribute to sarcopenia are lack of exercise and poor nutrition.

• Older adults spend most of their waking hours engaged in sedentary activities. Inactivity accelerates muscle breakdown and dysfunction, often leading to a vicious cycle of muscle loss, injury, and inefficient repair, causing elderly people to become increasingly sedentary over time. _[2]
• Many older Americans fail to consume the current recommended dietary allowance (RDA) of protein, which may not even be high enough for their needs._[3-5] Older people require more protein than younger people to stimulate the same amount of muscle growth._[6]

Diagnosing Sarcopenia

Sarcopenia is diagnosed using the criteria of low muscle mass and low muscle function (either low strength and/or low physical performance)._[1] The three most important tests for diagnosing sarcopenia are appendicular lean body mass, grip strength, and gait speed._[7]

Appendicular skeletal muscle mass. Imaging techniques used for estimating muscle mass include computed tomography (CT scan), magnetic resonance imaging (MRI) and dual energy X-ray absorptiometry (DXA). CT and MRI are gold standard methods but are rarely used because of their high cost, limited access, and concerns about radiation exposure. DXA is the method most often used in research because it is less expensive and exposes the patient to minimal radiation.

A practical alternative for measuring muscle mass, and one you can even use on your own at home, is bioelectrical impedance analysis (BIA). When used in clinics, BIA has been found to correlate well with body imaging techniques like MRI and is considered by experts to be an appropriate alternative to DXA in the diagnosis of sarcopenia._[8]

Home BIA machines are commonly called “body fat scales” or “body composition analyzers.” Most devices display some measurement of muscle mass, such as muscle mass percentage or muscle mass in weight.

Handgrip strength is currently the most popular, well-studied, and best-accepted way of assessing muscle strength and diagnosing sarcopenia._[9]

Grip strength accurately measures general upper body strength, and reflects overall strength, lower-limb strength, and performance._[11] It is positively and significantly associated with cognition, functional status, mobility, cardiovascular disease, and death._[12-14] Even in middle-aged people, grip strength is an accurate and consistent predictor of all causes of death._[15]

To measure hand grip strength, a person squeezes a dynamometer as hard as they can three times, with a one-minute rest between measurements. A highest value of <30 kg for men or <20 kg for women is the cut-off for diagnosing sarcopenia._[8] These values identify weakness associated with limitations in mobility._[16]

Dynamometers are available for personal purchase but are fairly expensive. If you don’t have access to your own, many doctor’s offices, health clinics, and fitness centers have dynamometers available for assessing strength.

Gait speed is a simple, well-documented marker of physical performance. To assess gait speed, mark off a six-meter course. Measure the time, in seconds, it takes to complete the walk at your usual pace. Walking aids are allowed.

Gait speed <0.8 meters per second denotes mobility impairment._[17] Gait speed ≤0.8 m/s is the recommended cut-off value in the diagnosis of sarcopenia and predicts subsequent disability, falls, cognitive decline, institutionalization, and mortality._[11,17]

Treatment Tips—Plus Advice on How to Prevent Sarcopenia

Protein supplementation, exercise, and vitamin D are the established, basic treatments for sarcopenia, even within the conventional medical system. A closer look:

• Protein: Consuming more protein from diet and supplements can help prevent and treat age-related muscle loss. Older adults who eat more protein have greater muscle mass than those who eat less, _[18] and middle-aged adults with higher protein intake have a significantly lower long-term risk of developing sarcopenia as they age._[19]Many nutrition experts want the current protein RDA of 0.8 grams per kg of body weight to be increased _[20] to at least 1.2 grams per kg of body weight._[21] People who exercise or have chronic disease need even more—around 1.5 grams per kilogram of body weight._[21]The type of protein and the timing of ingestion matter too. Spreading protein intake throughout the day is more beneficial for boosting muscle._[22] Older adults should consume around 25 to 30 grams of protein with each meal._[23]Different proteins have different amounts of amino acids. The amount of the amino acid leucine determines whether skeletal muscle protein stimulation can occur or not._[25]In general, animal proteins and whey protein contain more leucine than plant proteins._[26]Proteins that are more quickly digested and absorbed, such as whey, stimulate muscle growth better than proteins such as casein and soy.Liquid proteins are generally better for maximizing muscle growth due to faster digestion. Whey protein is typically consumed in a beverage, offers quick digestion, and has high leucine content, making it particularly good at promoting muscle synthesis. It is superior to soy protein _[27] and, when used with strength training, consistently increases muscle mass._[28]

  Pea protein is another promising option. One study found it to be nearly equivalent to whey protein._[29]Leucine supplementation can significantly increase muscle mass in the elderly and works particularly well in people with sarcopenia._[30] A study showed that a supplement containing just 6.25 grams of total protein plus 5 grams of leucine was as effective as 25 grams of whey protein at maximally stimulating increased muscle protein synthesis after resistance exercise._[31]

  At least 2.5 grams of leucine is typically needed to exert beneficial effects on muscle mass._[1] Combining leucine with other essential amino acids or protein sources is more effective than taking free leucine on its own.

• Exercise: Both aerobic/endurance and strength/resistance exercise help older adults improve their muscle health and overall health. While aerobic/endurance exercise is most helpful for ­maintaining and improving cardiovascular and respiratory function, strength/resistance exercise improves muscle strength, power, and function._[2] A combination of the two is recommended.Progressive resistance exercises, where participants exercise against an increasing load, can prevent or even reverse age-related loss of muscle mass and strength. A review found that progressive resistance exercise performed two or three times per week improved muscle strength, gait speed, physical ability, and functional limitation._[32]Adults over age 50 gain an average of 2.4 pounds of lean body mass with resistance exercise._[33]Even very old and frail people benefit greatly from progressive resistance training; one study showed that eight weeks of progressive weight lifting was associated with an average 174 percent gain in muscle strength, a 9 percent increase in the mid-thigh muscle area, and a 48 percent increase in gait speed._[34]Resistance training can be accomplished with traditional free weights and dumbbells, weight machines, body weight, elastic tubing, medicine balls, or even common household products like milk jugs filled with sand or soup cans.The American College of Sports Medicine (ACSM) recommends that older individuals who are less fit focus primarily on machine-based exercises as they are safer to use compared to more complex free-weight exercises._[35]

  A personal trainer is an excellent resource for establishing a progressive weight training program. Aim for two non-consecutive days per week.Exercise is most effective when coupled with proper nutrition, especially when resistance exercise is combined with higher amounts of protein._[36] Whey protein combined with resistance exercise leads to significant improvements in muscle mass, with average increases in lean body mass of 4.9 pounds._[37]

• Vitamin D: Another crucial component of sarcopenia treatment is vitamin D._[38] Vitamin D deficiency is associated with muscle atrophy, low handgrip strength, weakness, and sarcopenia._[39-41]Vitamin D supplementation alone and combined with a leucine-enriched whey protein supplement significantly increases strength and improves muscle mass and function in older adults with sarcopenia, even when no exercise is part of the intervention._[42,43]Vitamin D is best dosed according to your blood levels of vitamin D as measured by the 25-hydroxyvitamin D test. Most natural and integrative practitioners suggest that most people maintain blood levels of 25-hydroxyvitamin D between 50 and 80 ng/mL for optimal health. The daily dose needed to maintain these levels is 2,000 to 5,000 IU per day.

How to Prevent Sarcopenia: What to Try First

If you’re worried about losing muscle mass and strength as you age, remember that good nutrition, plenty of protein, and a regular strength training program are essential therapies. They’ll not only help to prevent sarcopenia, but will help keep you healthier, leaner, and free from chronic disease. Your take-away:

1. Make sure you’re getting enough dietary protein. Eat more fish, eggs, poultry, and lean red meat. If tolerated, also include fermented dairy, milk, and legumes. Meal replacement shakes can also be a good way to make sure you’re getting enough protein into your diet.
2. Next, focus on strength training. The combination of increased protein and strength training will increase muscle mass and strength more than either therapy alone.

These simple steps will provide the foundation for keeping you strong, mobile, and independent. Extra supplementation with protein powder such as whey protein (25-30 grams twice a day, including after exercise), leucine (2.5-5 grams per day), and vitamin D (to achieve and maintain blood levels of 50 to 80 ng/mL) can be added for even more powerful sarcopenia support.

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Originally published in 2016, this post is regularly updated.