While we tend to take for granted that the younger a person is, the more fit they are, that’s often not the case. Physical activity at any age is what determines physical fitness — not age — according to new research.
Exercise is the key, say the researchers. And it appears that the intensity of the exercise regimen may be more important than its duration.
The new study shows that by increasing the intensity of your exercise, you can beat back the risk of metabolic syndrome, the troublesome set of risk factors that can predispose people to type 2 diabetes, stroke and cardiovascular problems.
“Physical condition is the most important factor in describing an individual’s overall health, almost like a report card,” says Stian Thoresen Aspenes, who conducted the research at the Norwegian University of Science and Technology’s (NTNU) K.G. Jebsen Center of Exercise in Medicine.
The new study used information from 4,631 healthy men and women from Norway’s biggest health database, the Nord Trøndelag Health Study (HUNT) to examine fitness in adults from all age classes.
HUNT participants underwent laboratory tests in 2007-2008 to check their peak oxygen uptake, called VO2peak, which is used as a measure of overall fitness. This collection of information represents the largest database in the world of objectively measured VO2peak in healthy men and women aged 20-90 years old.
The detailed information from the database enables researchers to compare measures of fitness with cardiovascular risk factors and other assessments of overall health, giving them the statistical power to confirm what previous studies have suggested — that youth isn’t everything when it comes to being fit. Their data also show how those who were least fit also had the worst measures of cardiovascular health, such as higher blood pressures and higher cholesterol levels.
The underpinnings of the K.G. Jebsen Center’s research go back in time and far away in place, to Dallas in 1965, when researchers selected five healthy 20-year-olds to spend three weeks in bed, for what has become one of the most famous fitness studies of all, the Dallas Bed Rest and Training Study.
Predictably, the five 20-year-olds lost fitness after their three weeks of bed rest — with their measure of maximum oxygen uptake, VO2 Max, dropping by a whopping 27 percent. But it was what happened 30 years later, when researchers followed up on the study and retested these same men, which delivered the biggest surprise.
Time had not been so charitable to these men. On average, they had gained 23 kg, and their body fat percentage had doubled — so they were far from fit. But when researchers tested their peak oxygen uptake, it had dropped by only 11 percent as compared to their 20-year-old healthy selves.
When the current researchers looked at the importance of the intensity of exercise versus the duration, intensity was far more important than duration in determining peak oxygen uptake.
The research also looked at the benefits of high intensity exercise in the form of interval training, where four or more short periods (typically 4 minutes) of very high intensity exercise are followed by a similar number of short periods of lower intensity exercise. This approach, called 4×4 interval training, is a quick way to increase your overall fitness, research from the Jebsen Center has confirmed.
The researchers found that women whose fitness values were below the median VO2peak (<35.1 mL kg-1 min-1) were five times more likely to have a cluster of cardiovascular risk factors compared to those in the highest quartile of VO2peak (40.8 mL kg-1 min-1).
For men below the median (<44.2 mL kg-1 min-1), the risk was even higher — they were fully eight times more likely to have a cluster of cardiovascular risk factors compared to those in the highest quartile of VO2peak (50.5 mL kg- 1 min-1). Even small differences in VO2peak were found to be associated with worsening cardiovascular risk profiles.
The new research shows that maintaining some level of physical activity is important. The benefit from having been active when young is small if you are inactive now. “Even if you were highly active at a young age, you have to keep being active to get the health benefits from it,” says Professor Wisloff.
Source: K.G. Jebsen Center of Exercise in Medicine