New research from Europe has found older people are generally living longer and healthier lives than the previous generation.

Today, 75- and 80-year-olds in Finland appear to be physically and mentally fitter than they were 30 years ago.

Over the last few decades, human life expectancy has increased by an extraordinary amount. The average person born in the 1960s lived to around 52 - in Finland, they can now expect to live to over 80.

What's less clear is how many of those extra years are spent in good health with relatively good mental and physical function.

After all, a longer life doesn't necessarily mean more quality time, and some scientists worry that "years are being added to our lives" while "life is not being added to our years".

In light of this concern, the World Health Organisation (WHO) recently introduced a new metric known as health life expectancy (HALE).

It's a good step for a rapidly ageing global population, but coming up with a way to measure a healthy, functional life in old age is difficult. As such, current research on whether life expectancy is tied to better physical and mental health has turned up inconsistent results, and many of these studies are based on self-assessments.

Even research that uses objective measurements has provided uncertain results. While large, population-based studies in Europe show muscle strength is worse today among elderly people than it was in the past, other studies have shown grip, walking speed, and cardiovascular function has improved.

In Finland, researchers say they are in a unique position to dig further. Here, scientists have access to a population-based study on elderly people from the last generation, including 500 participants aged between 75 and 80.

Repeating the same physical and mental tests as were done 28 years ago, researchers found today's 75- and 80-year-olds show marked and meaningful improvements in grip strength, walking speed, and forced exhalation.

We still don't know why that is, but the authors have offered several possible explanations.

The earlier cohort of older people were born when Finland was still an undeveloped, agricultural region of the Russian empire, which means children likely had poorer nutrition and were more likely to work from an early age.

As they grew up, they experienced both a civil war and two world wars, one of which they may have participated in.

The more recent cohort, which included 726 participants, generally had a steadier upbringing, and this might have something to do with their greater height and weight, which is a sign of good nutrition and development.

In all likelihood, the authors argue, the results are a combination of better education, greater economic opportunity, and greater physical activity and nutrition.

"The cohort of 75- and 80-year-olds born later has grown up and lived in a different world than did their counterparts born three decades ago," says gerontologist Matti Munukka from Jyväskylä University in Finland.

"There have been many favourable changes. These include better nutrition and hygiene, improvements in health care and the school system, better accessibility to education and improved working life."

Not all changes have been good though. Interestingly, the lung function tests were somewhat mixed, with only exhalation improving significantly in the later cohort. The authors think this might have to do with the rise of smoking and environmental pollution.

In the end, however, the results suggest that older people living in Finland today can expect to live longer than they might have 30 years ago. In that same time, life expectancy in Finland has increased by three years among 75-year-olds and two years among 80-year-olds.

"Having more years to death at these ages, together with the current results, suggests that today's older people are functionally younger than people of the same age one generation earlier," the authors conclude.

This is great news, and there's better news for cognitive health. Compared to the mixed results of physical ageing, studies tend to show our cognitive health in old age is better now than it once was.

Luckily, the Finnish study from 28 years ago also tested participants on their cognitive health. Repeating these same tests nearly three decades later, researchers say today's cohort of 75- and 80-year-olds performed better in all measured outcomes.

This was true for both sexes, and the authors say the findings can be partially explained by longer education and a higher level of physical activity, which are known to shape and maintain cognitive performance as we age.

The team admits their findings will not stop the debate on whether we are, in fact, fitter in old age than we once were. They acknowledge that an increase in sedentary lifestyles and obesity may have adverse effects in the next generation of elderly people.

The team also points out that the lower participation rate in the more recent generation meant healthier people may have been the ones more likely to have participated. And of course this research is specific to Finland, a country that regularly tops multiple global social rankings - people in other countries face very different circumstances.

"The results may be unique to Finland," the authors caution, "however, it is likely that they can be generalised to other countries that have undergone similar societal changes during the last 100 years."

That said, the results are promising. Researchers in Finland were able to compare women and men of exactly the same ages using the same tests as 28 years ago, and that sort of rigorous methodology and long time span is precious in population-based health research.

"This research is unique because there are only a few studies in the world that have compared performance-based maximum measures between people of the same age in different historical times," says public health scientist Taina Rantanen, also from Jyväskylä University.

"The results suggest that our understanding of older age is old-fashioned. From an ageing researcher's point of view, more years are added to midlife, and not so much to the utmost end of life."

The study was published in Ageing Clinical and Experimental Research and the Journals of Gerontology.