Physical activity and exercise Archive

Your range of motion — how far you can move a joint in various directions — is determined by many things, starting with the inner workings of the joint and the structures surrounding it. Stretching exercises can help extend this range of motion. To understand how, it helps to be familiar with these structures and how they can help — or hinder — a joint's flexibility:

• Joints are the junctions that link bones together. The architecture of each joint — that is, whether its structure is a hinge, pivot, or ball-in-socket — determines how the bones can move.
• Muscles surround joints and provide the energy used to move them. The amount of tension in the muscles surrounding a joint is a key factor in how big of a range of motion that joint can achieve. Muscle tension can be affected both by passive factors, such as tissue scarring or your habitual posture, and by active factors, such as involuntary muscle spasms or purposeful muscle contractions.
• Tendons are flexible cords of strong tissue that connect muscles to bones and make movement possible. When a joint moves, energy from the muscles is transferred into the tendons, which tug on the bones.
• Ligaments are tough, fibrous bands of tissue that bind bone to bone, or bone to cartilage, at a joint. An example is the anterior cruciate ligament (ACL), one of five ligaments that together control the movements of the knee. Among other things, the ACL keeps the knee joint from rotating too far.

When you stretch, you're working muscles and tendons rather than ligaments. Ligaments are not supposed to be elastic. An overly stretchy ligament wouldn't provide the stability and support needed for a safe range of movement.

Another type of training, known as power training, is proving to be just as important as traditional strength training in helping to maintain or rebuild muscles and strength—maybe even more important.

As the name suggests, power training is aimed at increasing power, which is the product of both strength and speed, reflecting how quickly you can exert force to produce the desired movement. Thus, faced with a mountain hike, you may have enough strength to reach the summit. But can you keep up with the younger members of your hiking group? Power, not just strength and cardio fitness, can get you up the steep inclines quickly and safely. By helping you react swiftly if you trip over a root or lose your balance on loose rocks, power can actually prevent falls.

When you hurt, it's hard to persuade yourself to move. However, regular exercise not only helps maintain joint function, but also relieves stiffness and decreases pain and fatigue. What should you do? Whenever possible, meet the Physical Activity Guidelines for Americans by mixing aerobic activities, strength training, stretching, and balance exercises.  If this is too ambitious, at least avoid inactivity. Discuss options with your doctor, particularly if you haven't been exercising. A physiatrist, physical therapist, or personal trainer with experience in working with people who have arthritis can help you choose and adapt activities that will work for you.

You can also find programs specifically designed for people with arthritis. Examples include Fit and Strong!, a program targeted to older adults with osteoarthritis; the Arthritis Foundation's Exercise Program (AFEP); and its Walk with Ease program. There are also water-based therapy programs, such as the Arthritis Foundation's Aquatic Program, that are done in pools heated to nearly 90° F; these feature a variety of exercises, including range-of-motion exercises and aerobics. Another good option is tai chi, a low-impact, slow-motion form of exercise that can increase flexibility and muscle strength in the lower body, as well as aiding gait and balance. Strength training improves muscle strength, physical functioning, and pain.

Celebrities can certainly help raise awareness of health issues, but these stories can't replace medical advice based on your personal situation.

It's having the strength and motor skills to carry out the activities that get you through each day.

You may think of exercise as something you do to keep your heart and lungs healthy or to maintain your weight, and those are great benefits. But exercise is also important to keep you functioning throughout your day, whether you're carrying a laundry basket or playing with your grandkids. The ability to do such ordinary activities is called "functional" fitness, and programs to help people stay functionally fit are a top trend in the exercise world, according to the American College of Sports Medicine.

Yet many older adults aren't aware of this type of exercise program. "It's not on people's radar," says Clare Safran-Norton, clinical supervisor of rehabilitation services at Harvard-affiliated Brigham and Women's Hospital.

Ask the doctor

Q. I'm very overweight, and my doctor has been urging me to consider bariatric surgery. I'm worried that, like the diets I've tried, it will work for a while and then stop working. Am I being too cautious?

A. Bariatric surgery involves any of several different surgical procedures on the stomach and intestine designed to reduce the calories your body absorbs from the food you eat. It also helps quell appetite. That's because, in all of us, when our stomach becomes empty following a meal, it starts to make a hormone (called ghrelin) that travels to the brain and stimulates appetite. Bariatric surgery seems to diminish the amount of that hormone.