The physical activity a woman does before child-bearing etches itself into her cells in ways that mean the benefits of exercise can be passed on to later generations, including children and grandchildren – even if these younger generations do not actually exercise themselves.

So if your grandmother was fit and a regular exerciser before childbearing, you could be reaping the benefits of this.

These are the findings of a study that suggests that grandmaternal exercise has profound effects on the metabolic health of grand offspring as they age.

Conducted by a team of researchers at Harvard Medical School, the study shows that grandmaternal exercise improves glucose tolerance in adult male and female grandchildren, even in the absence of any exercise interventions undertaken by the offspring or grand offspring.

Scientists also observed that grandmaternal exercise was linked to decreased fat mass in grandoffspring, regardless of whether the grandmothers ate a healthy diet or a diet high in fat.

As a result, the study concludes that grandmaternal exercise has beneficial effects on the metabolic health of grandoffspring, demonstrating an important means by which exercise before and during pregnancy "could help reduce the worldwide incidence of obesity and Type 2 diabetes".

“We determined that there are striking effects of maternal exercise on the metabolic health of grand offspring as they age," said the study's lead author, Laurie Goodyear, professor of medicine at Harvard Medical School and senior investigator of Integrative Physiology and Metabolism at Joslin Diabetes Center.

"Our findings suggest that exercise during pregnancy may help prevent obesity and diabetes not just in offspring, but in grand offspring as well.”

The research observed two sets of males and females up to the age of one year old. In one group, the grandmother had been physically active, in the other, she had not been. In both groups, the parents of the males and females were inactive.

After studying the grand offspring for a year, the researchers observed that grandmaternal exercise was linked to decreased bodyweight and increased bone mineral density in second-generation male offspring independent of grandmaternal diet.

Second-generation male and females who had exercise-trained grandmothers also demonstrated lower fat mass.

When the researchers performed glucose tolerance tests, they found that second-generation males and females from sedentary grandmothers showed worsening glucose tolerance with age.

The grand offspring from exercise-trained grandmothers, however, did not have this age-related decline in glucose tolerance, having markedly better metabolic health compared to grand offspring from sedentary grandmothers. Grandmaternal diets also had little impact on glucose tolerance, with the major variable being exercise.

Ana Alves-Wagner, a senior post-doctoral fellow and a member of the research team, said: "While there has been growing evidence in recent years that maternal exercise can improve the metabolic health of first-generation offspring, remarkably, our current data demonstrate that maternal exercise has similarly robust effects to improve the metabolic health of second-generation, adult male and female offspring.

“Our work shows that exercise during pregnancy can be an important tool to improve the metabolic health of multiple generations, and could help to decrease obesity and diabetes worldwide.”

To read the full research, click here.