Exercise and Fitness Archive

Study after study has shown that Americans don’t get enough activity. In fact, many of us don’t even get our recommended 10,000 steps a day. Could pedometers or digital fitness trackers help? Pedometers are simple gadgets that measure how many steps you take. Digital fitness trackers also measure the pace, distance, duration, and intensity of your activity, and often have accompanying web applications that can evaluate and even graph this information. In a small study published in the American Journal of Preventive Medicine, researchers gave either a standard pedometer or a Fitbit brand digital fitness tracker to 51 overweight postmenopausal women who had been getting about 33 minutes per week of moderate to vigorous physical activity. The pedometer group did not have any significant change to their activity levels. But the fitness tracker group increased their physical activity by an additional 38 minutes per week.

It helps build cardiovascular fitness with shorter workouts.

Have you heard about interval training but aren't sure how it works and whether it's right for you? Interval training simply means alternating between short bursts of intense exercise and brief periods of rest (or a different, less-intense activity). The payoff is improved cardiovascular fitness.

A randomized controlled trial of Finnish women over 70 has demonstrated that regular exercise can significantly reduce the risk of serious injury from a fall. Researchers from Tampere University studied 370 women who had fallen during the previous year. They were randomly divided into two groups. One group of 187 participated in classes in which they learned exercises to increase strength, balance, and agility. They attended exercise class twice a week for a year and once a week the next year. They exercised at home on the days they weren't in class. The women in the control group continued their normal routines. All the women kept daily diaries in which they noted whether they had fallen, and if so, the type of injury they sustained and whether they required medical attention. They mailed their diaries to the researchers every month.

At the end of the period, the number of falls was about the same in both groups: 140 in the exercise group and 141 in the control group. The consequences of those falls, though, differed noticeably between the groups: women in the exercise group had 20 falls requiring medical attention, including eight fractures and six head injuries. That compared with 39 such falls in the control group, involving 14 fractures and 12 head injuries.

New study findings provide better guidance to men about treatment options for spinal stenosis.

Spinal stenosis, a progressive narrowing of the space around the lower (lumbar) spinal nerves, is a common cause of back pain and disability in men over age 65. When anti-inflammatory medications and injections fail, stenosis sufferers start looking for other solutions. A surgical procedure called decompression can improve things temporarily, but like any back surgery, it comes with risks.

Competition is great for older adults, but don't skip training camp before your season starts.

Tai chi appears to have positive effects on a wide range of thinking skills in healthy adults, such as attention, learning, memory, and perception.

Research suggests benefits for a range of cardiovascular conditions.

The world moves at a hectic pace these days. If you feel like you're constantly running on empty, you're not alone. Many people say that they just don't have the energy they need to accomplish all they need to. Sometimes the cause of fatigue is obvious — for example, getting over the flu or falling short on sleep. Sometimes a vitamin deficiency is part of the problem. It might be worth asking your doctor to check a few vitamin levels, such as the three we've listed below.

• Iron. Anemia occurs when there aren't enough red blood cells to meet the body's need for oxygen, or when these cells don't carry enough of an important protein called hemoglobin. Fatigue is usually the first sign of anemia. A blood test to measure the number of red blood cells and amount of hemoglobin can tell if you have anemia. The first step in shoring up your body's iron supply is with iron-rich foods (such as red meat, eggs, rice, and beans) or, with your doctor's okay, over-the-counter supplements.
   
• Vitamin B₁₂. Your body needs sufficient vitamin B₁₂ in order to produce healthy red blood cells.  So a deficiency in this vitamin can also cause anemia. The main sources of B₁₂ are meat and dairy products, so many people get enough through diet alone. However, it becomes harder for the body to absorb B₁₂ as you get older, and some illnesses (for example, inflammatory bowel disease) can also impair absorption. Many vegetarians and vegans become deficient in B₁₂ because they don't eat meat or dairy. When B₁₂ deficiency is diet-related, oral supplements and dietary changes to increase B₁₂ intake usually do the trick. Other causes of B₁₂ deficiency are usually treated with regular injections of vitamin B₁₂.
   
• Vitamin D. A deficit of this vitamin can sap bone and muscle strength. This vitamin is unique in that your body can produce it when your skin is exposed to sunlight, but there also aren't many natural food sources of it. You can find it in some types of fish (such as tuna and salmon) and in fortified products such as milk, orange juice, and breakfast cereals. Supplements are another way to ensure you're getting enough vitamin D (note that the D₃ form is easier to absorb than other forms of vitamin D).

For more ways to combat fatigue, buy Boosting Your Energy, a Special Health Report from Harvard Medical School.

Q . Can you explain exactly what "ejection fraction" means? And is there any way to increase it?

A. Ejection fraction refers to the volume of blood that's pumped out of the heart's left ventricle each time it contracts. Contrary to what many people believe, a normal ejection fraction is not 100%. Even a healthy heart pumps out only about half to two-thirds of the volume of blood in the chamber in one heartbeat. So a normal ejection fraction lies somewhere in the range of 55% to 65%.