ACSM reveals exercise guidelines

Guidelines for what constitutes the most effective exercise regimen have been elusive. Recently, the American College of Sports Medicine (ACSM) created a committee of medical and fitness experts to review the scientific literature and make recommendations.

The ACSM committee sought to provide guidance regarding the quantity and quality of exercise needed to remain fit and reduce the risks of developing disorders associated with inactivity. These conditions include heart disease, obesity, high blood pressure, stroke and diabetes.

Regarding the quantity of exercise, the group concluded that adults should perform a minimum of 150 minutes of moderate-intensity exercise each week. This should be in addition to limiting the amount of sedentary activities such as watching TV, reading and playing computer games.

The quality of exercise was divided into four categories:

• Cardiorespiratory Exercise: Also known as aerobic exercise, this category includes running, cycling, rowing, elliptical training and many other activities. The recommended 150 minutes can be divided over five days or three days. The frequency and intensity should be gradually increased.

• Resistance Exercise: The goal should be to train each major muscle group two to three days per week. Between two and four sets of 8-12 repetitions work best. Free weights, bands or machines are all acceptable modalities but the amount of resistance should be low at first.

• Flexibility Exercise: Stretching exercises are imperative before engaging in any fitness regimen. For many adults stretching should be performed upon awakening to avoid injured muscles through the course of a normal day. Each stretch should be held for 10-30 seconds and repeated two to four times.

• Neuromotor Exercise: This group of exercise is aimed at improving coordination and balance. It is particularly important as athletes grow older and has been proven to avoid falls. Activities including yoga, tai chi and dance are part of this group.

While these guidelines set an ideal goal, any activity is a “step” in the right direction.

Baseball players are most susceptible to lower back injuries

A review of the current Major League Baseball disabled list reveals five players out of action due to injuries affecting the low back.

Low back injuries involve the elements that make up the lower spine in addition to the muscles that provide support and strength. Due to the amount of sports-related repetitious movement involving the low back, injuries are common and very disabling.

The lumbo-sacral spine consists of five bony, lumbar vertebrae and the sacrum. Each vertebra is separated by a cartilaginous disc to provide a cushion. The entire structure is held together by a series of ligaments.

This elaborate design protects the spinal nerves contained within the bony spinal canal. These nerves exit the canal via small holes called foramina and proceed to provide sensory and motor function to the lower extremities.

The low back musculature connects the lower ribs, spine, pelvis and sacrum. It is the muscular system that provides the strength and stamina necessary for repeated movement.

The most common sports-related injuries are caused by sudden impact that compresses the spine and twisting injuries due to torque placed on the muscles and ligaments.

Low back strain results from torn muscle fibers. These injuries are best managed conservatively with rest, anti-inflammatory medications and physical therapy. Baseball players and especially pitchers are prone to these injuries given the need to generate throwing power by twisting.

Injuries that involve the intervertebral discs can result in breakage of the disc and protrusion of the broken piece. If the herniated disc compresses the spinal nerve, the athlete may experience symptoms of weakness, sensory loss and severe pain.

Treatment may involve decompressive surgery and a long rehabilitation. A rigorous regimen of stretching and back strengthening exercises often referred to as a “back program,” is the best way to avoid time on the disabled list.