Bone density and muscle mass: why they matter to athletes (2024)

Of course, running and cycling preserve leg muscle tissue, and studies have shown that running about 20 miles per week enhances bone density. Unfortunately, running has little impact on upper-body muscle mass, and scientific studies have shown that runners who log 40-75 miles per week actually may have decreased bone densities in their upper spines, shoulders and ribs, compared to sedentary individuals.

Since ageing leads to bone and muscle loss, and since running offers an incomplete protective effect (and a potentially negative effect for the upper part of the body), many exercise experts recommend that older athletes include resistance training along with their regular aerobic workouts. After all, weight training is an almost foolproof way to burgeon bone and muscle mass.

To see which plan - aerobic activity alone or aerobic activity plus strength training - is better for overall skeletal and muscular health, scientists at East Tennessee State University recently tested 43 healthy individuals who were all 55 years of age or older. Twenty-three of the subjects worked out three times per week for 30 minutes per session. Actual exercise consisted of walking vigorously on a treadmill, stair climbing or bicycling, with heart rates at 65-85 per cent of maximum during all of the workouts.

The other 20 exercisers performed aerobic activities (walking, stair climbing, bicycling) for only 15 minutes per day and spent the rest of their workout time strength-training all of their major muscle groups using weight machines. Resistance was always set at 5065 per cent of one repetition maximum - the greatest amount of weight which could be lifted successfully one time.

After four months, bone density (averaged over the whole body) and lean muscle mass increased significantly in the group which combined aerobic activity with weight lifting but didn't improve for the athletes who only engaged in aerobic exercise. In addition, the density of the 'femoral neck' - a part of the femur which links the straight shaft of the femur with the actual hip-joint socket - advanced for strength-trained athletes but stayed constant in the aerobic group. This is particularly important for older individuals, since the femoral neck is a frequent site of fractures.

Neither group was able to lift the density of the lumbar vertebrae, and each group improved the ability to do sit-ups and push-up by similar amounts. Although weight training is sometimes viewed as 'risky' for older athletes, none of the weight trainers was injured during the four-month study. Overall, a programme of aerobic activity plus strength training was better than aerobic exercise alone in terms of improving the integrity of the skeletal and muscular systems. As the researchers put it, 'We recommend that healthy people over the age of 55 years enrol in a combination of aerobic and weightlifting exercises'.

('Are Aerobic Exercises as Beneficial on the Musculoskeletal System as Weight-Lifting Exercises in Subjects 55 Years of Age and Older?' Journal of Aging-and-Physical-Activity, vol. 1(1), October 1993)

Why the muscles shrink with age - and what to do about it

Most peoples' muscles reach their maximum size during their 25th year of life, grow smaller by about 10 per cent between the ages of 25 and 50, and then shrink by 45 per cent over the next three decades. Why does so much muscle tissue disappear, and why does the degeneration accelerate after a half-century?

New research from Sweden has the answer. The primary reason for the sinew reduction is that the total number of cells in any particular muscle stays pretty constant until the age of 30 but then begins a steady decline. The fall-off is slow at first but increases dramatically after the age of 50. For example, if one of your muscles consisted of 100 cells (fibres) when you were 30, the muscle would probably still contain 90 95 fibres 20 years later, but the 'fibre count' would plummet to only 50-55 when you became an octogenarian.

Individual muscle cells in your body can be either type 1 ('slow-twitch') fibres, which contract slowly but have great endurance potential, or type 2 ('fast twitch') fibres, which contract quickly and powerfully but have little endurance. A decrease in the size of type 2 fibres plays a role in the muscle-shrinking process, with individual fast-twitchers shrivelling by about 25-30 per cent between the ages of 20 and 80. However, this loss is somewhat compensated for by the steadfastness of type 1 ('slow-twitch') muscle cells, which either remain unchanged in size or can expand by up to 20 per cent in individuals who remain very physically active as they get older.

What causes the fairly dramatic loss in muscle-cell numbers? Over time - and especially after the age of 50 - 'motor nerve cells' in the spinal cord begin to deteriorate at a steady rate. By means of their long arms, which spread outward from the spinal cord like the tentacles of an octopus, the motor nerve cells are normally in close contact with muscle cells. The motor nerves' key function is to 'tell' muscle fibres when to contract during physical activity, but the connection between motor nerves and their associated muscle cells is also necessary to keep the muscle fibres alive. As motor nerve cells die, the muscle cells to which they are attached also bite the dust.

Fortunately, there's a positive side to the story. People who participate in resistance training don't necessarily halt the fibre-death process, but they can stop and even reverse the tendencies of their type 2 cells to grow smaller. Although the number of muscle cells declines, type 2 (and sometimes even type 1 ) fibres may get larger as a result of strength training, leading to a potential advancement - instead of a loss - of total muscle tissue in the body. As a fringe benefit, resistance training in older individuals seems to increase the number of small blood vessels around muscles by up to 15 per cent, potentially increasing endurance capacity.

Since the overall process of muscle atrophy picks up steam after the age of 50, strength training for people over 50 is especially critical. Fortunately, it's never too late. Research demonstrates that even individuals over the age of 80 can fortify their muscles by participating in regular strength-training workouts.

('Ageing and Human Muscle: Observations from Sweden': Canadian Journal of Applied Physiology, vol. 18(1),pp2-18, 1993)

Bone density and muscle mass: why they matter to athletes (2024)


Bone density and muscle mass: why they matter to athletes? ›

The missing muscle makes it more difficult to run, cycle or swim powerfully, and the shrinking bones increase the likelihood of injury and osteoporosis.

Why is bone density important for an athlete? ›

There are also potential performance consequences of poor bone health, such as the development of stress fracture injuries. These are important injuries for the athlete that can result in a significant loss of training time [9], which undoubtedly impacts upon sporting performance.

Why is muscle mass important for athletes? ›

Further research indicates that stronger athletes produce superior performances during sport specific tasks. Greater muscular strength allows an individual to potentiate earlier and to a greater extent, but also decreases the risk of injury.

What do bones and muscles do for an athlete? ›

Bones, muscles and joints make up the musculoskeletal system, along with cartilage, tendons and ligaments. This system gives your body its structure and support, lets you move around and protects important organs. Injuries and many illnesses can damage bones, muscles and joints.

What are the benefits of building muscle mass and bone density? ›

By stressing your bones, strength training can increase bone density and reduce the risk of osteoporosis. Manage your weight. Strength training can help you manage or lose weight, and it can increase your metabolism to help you burn more calories. Enhance your quality of life.

Why is bone mass density important? ›

Other terms used for bone density are bone mineral density (BMD) and bone mass. Bone density is an important indicator of how likely bones are to break. It's also valuable in identifying osteopenia and osteoporosis and assessing the effectiveness of treatments that aim to prevent bone loss.

How does bone density affect exercise? ›

Because bone is living tissue, it changes over time in response to the forces placed upon it. When you exercise regularly, your bone adapts by building more bone and becoming denser. This improvement in bone requires good nutrition, including adequate calcium and Vitamin D.

What is a good muscle mass for athletes? ›

A good lean muscle percentage range should be about 70% to 90% to be considered healthy. That means your body fat percentage ranges from 10-30%. Athletes typically range in the 7-22% body fat for maximum performance. Men tend to be on the higher side with lean mass in 80-90% range and woman in the 70-85% range.

How does muscle mass affect performance? ›

An increase in lean body mass contributes to strength and power development. Strength and power are related to muscle size. Thus, an increase in lean body mass enables the athlete to generate more force in a specific period of time.

Why does muscle mass matter? ›

Healthy muscles let you move freely and keep your body strong. They help you to enjoy playing sports, dancing, walking the dog, swimming, and other fun activities. And they help you do those other (not so fun) things that you have to do, like making the bed, vacuuming the carpet, or mowing the lawn.

What is the fastest way to increase bone density? ›

11 ways to increase bone density naturally
  1. Weightlifting and strength training. ...
  2. Eat more vegetables. ...
  3. Consume calcium throughout the day. ...
  4. Eat foods rich in vitamins D and K. ...
  5. Maintain a moderate weight. ...
  6. Avoid a low calorie diet. ...
  7. Eat more protein. ...
  8. Eat foods rich in omega-3 fatty acids.

Does bone structure affect athletic performance? ›

If bone density is also lost, a decline in performance is a natural result. However, it doesn't need to happen. Athletes know that if they work to build muscle, they will enhance performance levels even as they age. The same applies to bone.

Does bone size affect muscle size? ›

While bone size can play a role in overall body size and shape , it does not determine the potential for muscle growth .

Why is muscle and bone strength important? ›

Preserving muscular strength/power in middle and older age is associated with a reduced risk of all-cause and cardiovascular mortality. Impaired muscular strength/power and balance is associated with an increased risk of falls and lower bone mineral content.

Why is muscle density important? ›

Building muscle density can improve athletic performance, bone health, and metabolism and reduce the risk of chronic diseases. Genetics, age, gender, diet, and exercise routine affect muscle density. Resistance training, progressive overload, and proper nutrition are essential for building muscle density.

Why is bone density important for a healthy life but more importantly for an athlete? ›

Key Points. Athletes need to pay more attention to their bone health, in the short term, to reduce the risk of injury, and in the long term when they have retired from the sport. The general diet required by the athlete to support bone health is not markedly different from the general population.

Why is it important to maintain bone density? ›

Bone density is vitally important as we age because less-dense bones are more likely to break, even from a routine, run-of-the-mill injury like tripping and falling off a curb.

How do strong bones help athletes? ›

Taking care of and building strong bones right from the start will help prevent sports injuries, improve overall health, and reduce the risk of osteoporosis later in life.

What does bone density do to the body? ›

Low bone density can lead to serious medical conditions that could result in bone fractures. The most worrisome condition is osteoporosis, where low bone density causes holes inside the bone to widen and the outer walls of the bone (the cortex) to thin. This causes the bone to be more fragile.

Why is increased bone density good? ›

A bone mineral density (BMD) test measures calcium and other minerals in bone. Bones containing more minerals are denser, so they tend to be stronger and less likely to break. Bones can become less dense as we age or if we develop certain medical conditions. When too much bone is lost, osteoporosis can develop.

Top Articles
Latest Posts
Article information

Author: Ouida Strosin DO

Last Updated:

Views: 6337

Rating: 4.6 / 5 (76 voted)

Reviews: 91% of readers found this page helpful

Author information

Name: Ouida Strosin DO

Birthday: 1995-04-27

Address: Suite 927 930 Kilback Radial, Candidaville, TN 87795

Phone: +8561498978366

Job: Legacy Manufacturing Specialist

Hobby: Singing, Mountain biking, Water sports, Water sports, Taxidermy, Polo, Pet

Introduction: My name is Ouida Strosin DO, I am a precious, combative, spotless, modern, spotless, beautiful, precious person who loves writing and wants to share my knowledge and understanding with you.