How exercising women cut risk of heart disease in old age

As human beings age, their immunity usually wanes and makes them susceptible to various ailments. 

The risk of cardiovascular diseases for instance, which refer to a range of ailments affecting the heart and blood vessels, tend to increase as people grow older.

A major contributor to the enhanced risk is the loss of muscle strength, which happens gradually as people age.

To minimise the risk of such complications during old age, health experts urge people to take up physical activity and ensure that their exercise regimes incorporate strength-training workouts during their younger years.

Strength exercises are activities that make muscles work harder than usual. This increases people's muscle strength, size, power and endurance.

The activities involve using one's body weight or working against a resistance. It is recommended that people try to do two sessions or more, of muscle strengthening exercises weekly.

Examples of such workouts include lifting weights, working with resistance bands, climbing stairs, hill walking, cycling, dance, push-ups, sit-ups and squats.

These strength exercises are extremely important for women as research indicates that in their old age, it becomes difficult for their muscles to develop small blood vessels, known as capillaries, which offer protection against cardiovascular diseases.

According to a new study published in the Journal of Physiology, capillaries in the muscles of women after menopause are less able to grow compared to young women.

"This means exercising before menopause is all the more important for women in order to develop blood vessels in muscles, and thus the ability to develop muscle strength," noted the researchers.

Recent studies have shown that there are some substantial differences in the way the blood vessels, which influence susceptibility to conditions like heart disease and stroke, are affected by aging and physical activity between women and men. 

This is a difference, which to a large extent is related to the female sex hormone, oestrogen.

The hormone is protective of the heart and blood vessels in women for about half of their lives. However, at menopause, there is an abrupt permanent loss of oestrogen, leading to a decline in the health of their blood vessels.

During the study, researchers from the University of Copenhagen studied older women (over 60 years old) and young ones (around 25 years old) ones.

The women were subjected to eight weeks of cycling training. And they performed the activity three times per week at moderate to high intensity.

Results showed that when the aged women completed the exercises, they did not achieve an increase in the number of capillaries ( small blood vessels) in their thigh's skeletal muscles. 

This is in contrast to what has been repeatedly shown in young and older men.

The number of capillaries in skeletal muscles can change a lot and is mainly affected by how much the muscles are used, such as during exercise.

Aging is known to lead to a loss of capillaries in the muscle. Past research has shown that in elderly men, this effect can be counteracted by a physically active lifestyle.

But this new study suggests that women do not attain capillary growth as readily during old age, after menopause. 

Yet, capillaries in skeletal muscles are very important for proper body functioning, physical capacity and general health. 

Their loss can affect the body's ability to regulate blood sugar, thereby leading to the development of type 2 diabetes and other conditions that increase the risk of cardiovascular diseases in older women.

"It is important to underline that both men and women have a vast benefit from being physically active throughout life, regardless of age. But the current study supports the idea that women may benefit from being physically active before menopause, while they still have oestrogen, so that they have a good physical starting point as they get older," noted the researchers.

A 2018 study published in the Medicine and Science in Sports and Exercise journal found that individuals who did any amount of strength training on a weekly basis had a 40 to 70 per cent reduced risk of developing heart attacks, strokes, or death related to heart disease compared with individuals who did no strength training.

In a related study, published in the Mayo Clinic Proceedings journal, researchers reported that having moderate muscle strength reduced type 2 diabetes risk by 32 per cent, independent of individuals' cardiovascular fitness levels.