Four interesting studies supporting the benefits of physical activity have appeared in recent medical journals:

Activity level and lifespan: The Women’s Health Initiative Objective Physical Activity and Cardiovascular Health study (OPACH) followed 5,446 women, 63 and older, for more than eight years (J of Aging and Physl Activ, Aug 24, 2022). The participants wore accelerometers for up to seven days at a time to measure:
• the time they spent moving,
• the intensity of physical activity, and
• the amount of time spent sitting.
The researchers found that higher levels of light physical activity and moderate-to-vigorous physical activity were associated with reduced risk of death and the more time spent sitting, the shorter the lifespan. This association was stronger than the association with how long their parents and other family members had lived.

Handgrip strength predicts risk for death: Testing a patient’s handgrip strength can be used as an additional test to predict how long an older person will live (BMJ Open, August 10, 2022). The study used a Smedley spring-type hand dynamometer to assess the handgrip strength of 8,156 U.S. adults aged 50-80 years and found that decreased handgrip strength for age was associated with decreased remaining years of life. The authors suggest that a sudden drop in muscle strength may be a sign that a physician should look for a harmful condition or disease. It can be used by doctors as they use blood pressure as a sign of impending heart disease.

Underweight in older women and overweight in older men associated with increased dementia risk: A study of 296,767 patients, average age 70.2 years, followed in one of 832 general medical practices in Germany for 10 years, found that women who were underweight and men who were overweight were at increased risk for dementia (Journal of Alzheimer’s Disease, Aug 23, 2022;88(2)). The study suggests that cognitive impairments should be regularly assessed in both underweight and overweight patients.

Older people with small muscles are at increased risk for future loss of mental function: A study of 8279 adults, 65 to 86 years old, found that having low muscle size is associated with significantly faster loss of executive function over three years (JAMA Netw Open, July 1, 2022;5(7):e2219926). This study showed that having small muscles is associated with faster loss of mental function. Many previous studies show that older people who have low muscle size and strength are more likely to suffer loss of mental function.

My Recommendations
You do not need to have a specific exercise program to stay fit; you just need to keep on moving for a large part of each day. It is healthful to mow your lawn, wash your dishes, make your bed, vacuum your house, go for a walk, and participate with your friends in activities where you are moving your arms and legs – dancing, cycling, swimming, running, nature walks and so forth. To gain maximum health benefits from your skeletal muscles, I recommend including some sort of resistance exercise. If you are not already doing strength training, first check with your doctor to make sure you do not have any condition that may be harmed by exercise.

Caution: Intense exercise can cause a heart attack in a person who has blocked arteries or heart damage. Check with your doctor before you start a new exercise program or increase the intensity of your existing program.