News Category: General

Weight lifting has been shown to help reduce the bone loss that often happens with menopause. Until lately, however, it was not clear which method of weight lifting helped bones the most: lifting small amounts of weight with a lots of repetitions, or using more weight and fewer repetitions.

The question of osteoporosis is on the minds of many women over forty. Menopause signals a significant drop in estrogen and other hormones that support and maintain bone strength throughout a woman’s lifetime. It is estimated that in the early years after these hormones drop, a woman may loose up to 5% of her bone density per year. Though there are medications that can reverse some bone loss, much of this loss is irreversible.

One way of preventing this loss is through muscle strengthening exercises. The bones respond to muscles tugging on them by releasing bone-building chemicals, resulting in denser bones. Or at least that’s the hypothesis.

So is it better to lift in the style of Arnold Schwarzenegger–or will a Pee Wee Herman approach suffice? Researchers addressed this question to see which kind of weight lifting impacted bone density the most.

Twenty-five women with an average age of 51 (all from one to seven years postmenopausal) were selected. There were two main requirements for participation in the study. Participants could not be on estrogen replacement therapy, and they were not to have done any resistance training in the past six months. The women were divided into three groups. One group served as a control group and didn’t do or change a thing. The other two groups began an exercise program. High-intensity exercisers did twice as much weight and half as many repetitions as the women doing low-intensity exercises.
 
Subjects were trained on proper upper and lower body weight lifting techniques. Both groups trained three days a week for six months. Their workouts included a 10-minute warm-up, a 45-minute weight lifting session, and a five-minute cool down. 

How did the exercisers fare? Both groups ended up having stronger muscles, but not stronger bones. Yet neither group showed a loss of bone. Past studies spanning nine to 12 months have shown measurable improvements in bone density. This made the authors question whether the women in their study would have shown higher bone densities had this study lasted longer.

The fact that these women gained stronger muscles is still good news. Better muscle strength means better balance and coordination, which helps lower the chances of falling and fracturing a bone. So the bottom line is that the styles of lifting used by Pee Wee and Arnold both seem to help keep women’s bones strong.

We all know that exercise is good for us. It tones the body and improves cardiovascular function. Researchers have also found that exercise may even boost your immune function–unless you exercise too intensely.

Swedish researchers tested rats to see how different levels of exercise affected the immune system. The rats were kept in separate cages. One group had cages without exercise wheels. Cages of the other rats had exercise wheels. Researchers tracked how much and how far each rat ran.

Those in the rat race followed a running schedule. They ran every day for either five or 11 weeks straight. Or they started out running every day for five weeks and then ran only four days a week for the final six weeks. At the end of the study period, the rats were injected with cancer cells that congregate in the lungs. Researchers then checked the rats’ lungs to see how well their immune systems had managed to clear the cancer cells.

All of the running groups showed better immune function than the sedentary group. The rats that ran every day for 11 weeks showed the poorest clearance of cancer cells of all the running groups. The researchers also grouped the rats by how far they ran each day. All of the runners showed better immune function than the sedentary group. And the rats that ran more often showed better immune function than the rats that ran the least.

The authors conclude that exercise–at least in rats–does seem to boost immune function. But the study also shows that doing too much training for too long seems to erode the benefits. It’s hard to make conclusions for humans based on animal studies. But the authors say that their results suggest there should be more research on “the important role of adequate rest in prevention and treatment of overtraining in humans.”

Building strength during the upward climb of adulthood may yield improved health on the other side of the hill. The results of this research article caution young and middle-aged adults to work on their strength and endurance now–before heading into their golden years. People who do no activities to strengthen their muscles are at risk for more physical limitations later in life. The advice usually given to elderly people to stay active appears to be equally important for young and middle-aged adults.

Researchers measured the physical strength and fitness of 3658 healthy men and women. They were scored in bench and leg press, sit-ups, and treadmill tests. Over about five years, everyone in the study answered questions about their physical abilities. People who were weaker when first tested were found to have more physical limitations at the time of follow-up. New health problems caused some of these limitations. However, poor strength and aerobic fitness scores were also important factors in whether people developed functional limitations.

Adults of all ages are encouraged to keep physically fit. The authors conclude that people should do both aerobic exercise and activities to strengthen muscles to avoid limitations in their later years. So maybe Jack and Jill should fetch a few extra pails of water before they hit the top of the hill, to avoid tumbling down the other side.

Muscle strains are a common type of injury, especially among sports participants. Even in this high-tech era, diagnosing and treating these injuries remains somewhat low-tech. For the most part, health care providers can usually determine if a muscle has been strained, torn, or ruptured simply by getting a history and examining the sore area. In some rare cases, an MRI scan may be needed to precisely locate the area that has been injured. (An MRI uses magnetic waves to show pictures of the soft and hard tissues of the body.) The time it takes the injury to heal depends on how bad the tear is. Minor tears often heal quickly. If more muscle fibers and deeper tissues are torn, the injured muscle may not respond as well to treatment and often takes longer to heal.

Common remedies for most muscle strains are resting the muscle and applying cold treatments. The authors report that cold treatments can be very helpful for easing pain, but they don’t always reduce swelling. If it’s too cold, the treatment can trigger the body to actually pump extra blood to the area, making the swelling worse. Compression and elevation also seem to help and are often recommended for pain and swelling. But the authors point out that there are no studies to prove this.

The authors also reviewed the benefits of using nonsteroidal anti-inflammatory drugs (NSAIDs) for muscle strains. Although NSAIDs may prove helpful for pain and swelling after the injury, the authors caution that long-term use of these medications might actually do more harm than good. According to the article, most experts agree that physical therapy treatments help patients regain flexibility and strength in the injured muscle.

Muscles that are flexible and strong are not as likely to become strained. When they are fatigued or are not properly warmed up, injury is more likely. With this in mind, the authors conclude that people who are recovering from a muscle strain should be sure to regain good strength and flexibility in the muscle before going back to more demanding activities. They should also start by warming up the muscle and then avoid overworking it when doing physically demanding activities.

Snow conditions, temperature, and kids’ attitudes about risk-taking have a big influence on their ski safety, among other factors. Studying these factors is a mogul-sized task. By snowplowing through the many possible risks faced by kids who ski, these researchers attempted to pinpoint the ones that seem to matter the most. By discovering these risks, better safety programs for young skiers can be offered.

Researchers targeted four possible risks that parents and young skiers could change once they learned about them. The four risk areas were lack of formal ski instruction, poorly adjusted bindings, rented equipment, and low skill levels. Information was collected during the 1995-1996 ski season at a large ski area in Canada. A total of 387 youths were assigned to either an injury or control group. The authors sent a survey to the parents of young skiers between the ages of three and 12, and children who skied by themselves were also invited to be part of the study.

When compared to the control group, the injured skiers tended to have low skill levels, use rented equipment, and have poorly adjusted bindings. Skill level mattered the most. Skiers with low skill levels had more injuries. However, formal ski instruction did not seem to have an affect on whether a child was injured. The authors suggest that future studies might show when and where young skiers with low skills are most often injured.

Skiers who used rented equipment also had a higher risk of injury, possibly because they are less skilled than those who own their equipment. Another reason might be that rented equipment is lower quality and not fitted properly. Also, poorly adjusted bindings were a factor in many of the injuries.

According to the authors, parents should be aware that poorly fitted equipment and low skill levels increase the risk of injury in young skiers. They also suggested that ski shops practice a standard way of fitting equipment and adjusting bindings for each person.

By strengthening bones during their teenage years, people may be better prepared to ward off the harmful affects of osteoporosis later in life. It is well known that bone health is improved by doing weight-bearing exercises. The authors put these two ideas together to develop the first study of its kind, a test to see whether high-intensity jump training could strengthen the skeletons of teenage girls.

The authors assigned 56 ninth-grade girls to two groups, an exercise group and a control group. At the beginning, all participants filled out surveys about their diet and took tests of balance, strength, and power. Bone mineral density testing was done to check the amount and quality of the bones in various parts of their skeletons. These measurements were used to track how the specialized exercise program affected bone health.

For the first three months, the girls in the exercise group prepared their muscles by doing graded resistance exercises. They also advanced through a series of jump training, called plyometrics. This specialized training is an effective way to improve muscle strength and power, but it has not been tested to see whether it can strengthen bones. Participants received high school credit for exercising up to 45 minutes, three times each week. The control group did their routine activities but did not do any specialized exercises.

After nine months, participants repeated the tests of balance, strength, power, and bone density. For the most part, the bones of both groups showed improvement, which might have to do with normal growth patterns. However, compared to the control group, the exercisers showed a lot more bone strength in the upper part of the hip, had up to 29% better side-to-side balance, and had better leg strength.

Based on these measurable improvements and the consistent participation with the program, the authors conclude that “high school PE programs could include plyometric training and potentially reduce future risk of hip fracture.”

By keeping a close eye on the rearview mirror of time, researchers have traced what happens after an injury to a hip or knee joint. When a joint is injured in a person’s early years, the chances of having future osteoarthritis (OA) in that joint increase.

Researchers tracked 1337 medical students graduating from Johns Hopkins University in Baltimore between 1948 and 1964. When the study first began, 64 participants reported having injured a hip or knee joint. The average age at injury was 16. Significantly, 13.9% ended up with OA, compared to only 6% of the participants who didn’t have injuries before the study. Also, people who injured their hip or knee joint over the course of the study were much more likely to end up with OA in the injured joint.

Clearly, people who have had an injury to the hip or knee joint, especially in their earlier years, are at higher risk for developing OA. Accordingly, the authors believe these people should be targeted for programs to prevent OA, and younger patients who have had a joint injury should be shown ways to limit extra strain on that joint. They conclude by encouraging doctors to “advocate use of proper sports equipment under safe conditions to prevent joint injuries” to avoid future problems.

Reports abound about the effectiveness of glucosamine and chondroitin, granting them newfound stardom in the treatment of osteoarthritis. But as the stardust settles, the actual benefits appear to fall short of the hype.

Researchers recently pooled the best studies done on these two supplements between 1966 and 1999. The studies tested these compounds in the treatment of hip and knee osteoarthritis over at least four weeks.

After plotting the details of the studies, the researchers found that the study methods could exaggerate the actual benefits. Also, the fact that manufacturing companies sponsored nearly all studies made the researchers concerned that the actual benefits might be inflated. When the authors looked at only the highest quality research, the actual benefits of these compounds were the smallest.

The authors note that these compounds are safe and that they do show some benefits. So even if glucosamine and chondroitin don’t live up to their star billing, they may still play an important role in treating the symptoms of osteoarthritis.

Rookies entering the minor leagues run a greater risk of injury than veteran players, according to this study. The authors say that rookies may not be prepared physically for the new demands of higher levels of play. Playing at such a high level requires the tissues of the body to adapt over a longer period of time. Rookies simply haven’t made these adaptations, which could account for their higher injury rates.

By reviewing the injury reports of six minor league teams from 1985 to 1997, the authors were able to compare how often players of different experience levels were injured. The rate for rookies was calculated at 2.42, a significantly higher rate than the 1.62 figure for veteran players.

The researchers also categorized how bad the injuries were to see who suffered the worst injuries. Even though the differences were slight, veteran players tended to have less severe injuries than rookies.

The authors suggest several reasons why rookies were injured more often. The authors believe longer seasons, insufficient training, and extra effort during high school or collegiate play may put players at risk of overuse. Then when they enter professional careers, their tissues are more likely to get injured. New injuries could also be related to injuries that happened earlier in players’ careers. The lower numbers of injuries in veteran and higher-ranked players could have to do with better training than in amateur levels of play.

To help offset the risks of injury for rookies, the authors suggest that they undergo specially designed strength and conditioning training before moving to a higher level of competition. The authors also recommend that players who move up be tested to see what kind of conditioning program will help the most.