Osteoporosis prevention and treatment has long focused mainly on women. It is true that men build larger and stronger bones early in life and are less likely to develop this disease, which is characterized by less dense, brittle bone mass more susceptible to fracture. Yet according to the National Osteoporosis Foundation, two million men currently have osteoporosis and another 12 million with low bone mass are at risk. Clearly a focus on prevention is also important for men, and osteoporosis is likely underdiagnosed in this gender and certainly not as extensively studied. There are many steps you can take to ensure optimal bone health, with a few considerations specific to you as a male cyclist as well.

Healthy hormones
In men, testosterone is the hormone responsible for maintaining strong bones (while estrogen performs this function in women). Intense endurance training and diet can impact hormone levels. “Cycling is a very catabolic exercise, and male cyclists may not take in enough energy for training. This can result in both bone and muscle loss due to decreased thyroid function, decreased production of testosterone, and increased cortisol,” said Dr. Michael Ross author of Maximum Performance for Cyclists and team physician for Navigators Insurance Cycling.

While female cyclists have a clear marker of estrogen deficiency with absent menstruation, markers of low testosterone in male cyclists may not be as obvious. Blood testosterone levels can fall from long periods of training and resting levels may be lower in highly trained male endurance athletes. One recent study compared serum hormone levels in road cyclist to weight lifters and a control group. The elite cyclists had lower total and free testosterone levels than the other two groups. Testosterone levels do naturally decline with age in men, but men do not experience the accelerated bone loss that menopause triggers in women. But after age 65, men and women experience a similar rate of bone loss.

Weight bearing is best
Cycling is not considered a weight bearing sport, though it does put some pressure on the spine. Experts agree that you need to incorporate some weight bearing activity into your training program year round.

Once study measured the bone mineral density of highly trained master cyclists who had been training and racing for an average of twenty years with little or no weight bearing exercise. Total body bone mineral density and bone mineral density of the spine and hip was significantly lower in the master cyclists when compared to younger cyclists and age-matched controls.

Resistance training clearly provides a whole body weight bearing activity that can be practiced year round. However you and/or your coach may not make as much time for resistance training during the peak of racing season. “While cycling is not a weight bearing exercise, high power, low volume intervals likely offer some protection. It is the long, low intensity miles that increase risk,” said Dr. Ross.

The type of on-bike training may also affect bone mineral density. In a study that compared cross-country mountain biker to road cyclists and recreationally trained men, the mountain bike cyclists were found to have a higher level of bone mineral density. This may suggest that mountain bike training could provide some type of bone stimulus not always incorporated into road cycling training. More data on various types of cycling workouts and effect on bone mass is needed, so in the meantime, incorporate resistance training and other weight bearing cross-training activities.

Nutritionally speaking
Along with proper weight bearing training and normal hormones levels, adequate intake of specific nutrients can go a long way to building bone mass and keeping bones strong. Calcium of course is of primary importance in contributing to a strong bone matrix. Make sure that your daily calcium intake is adequate as most men and women consume under 1,000 milligrams daily. Aim for more food sources of calcium, but supplement if needed. Don’t exceed 1,800 milligrams daily between food and supplement calcium sources. You can only absorb 500 milligrams of calcium at one time, so consume food sources and supplements throughout the day for best results.

It is important that you think beyond calcium for building healthy bone. Vitamin D helps absorb calcium and deposit it in the bones. If you consume too little, you absorb only 15 percent of the calcium consumed (versus the usual 30 percent). We can convert 15 minutes of sunlight to adequate vitamin D, but we are less efficient at this conversion as we age, and from November to April sunlight in much of the Northern Hemisphere is inadequate. Sunscreen does block vitamin D production and natural food sources are limited. Most multivitamins and calcium supplements include vitamin D.

Many experts agree that current recommended amounts are too low and older adults especially should aim for up to 800 IU daily. For healthy adults consuming vitamin D fortified foods and adequate and safe exposure to sunlight are essential to maintain optimal levels of blood vitamin D. An Adequate Intake (AI) exists for vitamin D (rather than an RDA) and is listed on food and dietary supplement labels as either micrograms (ug) or International Units (IU). The AI for men and women ages 14 to 50 is 5 ug (200 IU) and for ages 51 to 70 is 10 ug (400 IU). Adults over age 71 years require 15 ug (600 IU). However, in the absence of sunlight, some researchers believe that intakes of vitamin D should be closer to 25 ug (1000 IU). Some people may require dietary supplements to meet their daily AI for vitamin D.

Fortified foods are common sources of vitamin D. One 8-ounce serving of milk provides 2.5 ug (100 IU) of vitamin D. Sun exposure is probably the most important source of vitamin D, but exposure is often limited or avoided to prevent illness related to excess sun exposure. An initial exposure of 10 to 15 minutes allows adequate time for vitamin D synthesis in most light skinned persons, and perhaps two to three times longer in darker skinned persons, though some experts recommend no sun exposure without sunscreen.

Vitamin D intake from food and supplements combined should not exceed 50 ug (2,000 IU) for children, adults, and pregnant and lactating women. Excess vitamin D levels are unlikely to result from sun exposure and dietary intake, but rather from high intakes of vitamin D in supplements.

Other important nutrients include the mineral magnesium, which is needed for bone formation. Vitamin K activates osteocalcin, a protein needed for optimal bone strength. Vitamin C is needed for collagen formation, a substance that helps keep bone together. Good food sources of these nutrients are listed below. A high intake of fruits and vegetables is also associated with stronger bones.

Some dietary factors are actually harmful to calcium absorption. Excess sodium and caffeine can both increase calcium excretion. Alcohol can also be harmful to bones. High intakes of phosphorus, namely from carbonated beverages, should be avoided as too much of this mineral can upset calcium balance in the body.

Focusing on weight bearing exercise and adequate intake of specific nutrients helps to prevent primary osteoporosis, a process that is much likely to occur later in life for men than women. Other risks factors for secondary osteoporosis, which can occur in younger men include certain disease states such as gastrointestinal disorders and use of certain medications such as long term glucocorticoid treatment, that can adversely affect bone mass. Whatever the reason, prevention or early treatment is best, consult with your physician.