I’m back with another piece of interesting research which was recently published. Interesting not because of its conclusion, which seems obvious to those who have lived a physically cultured life. But interesting because of the size of the study and the age of the population studied. A Brazilian group recently published an absolutely massive study that asked the simple question: How does force impact death? More precisely, they were interested in the relationship between a simple measure of strength (handle dynamometry) and all-cause mortality. And they did it on 1980 adults, men and women, aged over 90. And about five years after the handle test, they went back to see what the survivor rates were like.

This type of research is considered a prospective cohort study, meaning the researchers measured a group of people (in this case, grip strength) and had in mind an outcome (all-cause mortality) that they would follow over a certain period. period (~5 years). When conducting this type of research, the outcome measure is what is called a “risk ratio.” This can be thought of as the probability of something happening. In the case of this study, whose endpoint was all-cause mortality, a hazard ratio of 1 would mean that there is no association between grip strength and death. Anything greater than 1 is more likely to lead to the outcome, anything less than 1 is less likely to lead to the outcome. And it’s all based on a percentage, with the difference between 1 being the percentage more or less likely. For example, a risk ratio of 1.3 is 30% more likely, while a risk ratio of 0.7 is 30% less likely to achieve the outcome. There you go, now you know the epidemiology.

So what did they find? For starters, they found that men’s median grip strength was 26 kg (~57 lbs) and women’s was 16 kg (~35 lbs). In what context does this take place? Well, it’s hard to say. There are no real standards for individuals this old. But, looking through some of my exercise physiology textbooks, I discovered that the norm range for 70 to 99 year olds is 21.3 to 35.1 kg for men and 14.7 to 24 .5 kg for women. So we could say that they were probably average given that they were at the upper end of that age range. Regarding the associations found, the researchers noted that those in the 90th percentile (i.e., top 10 percent strength) were 25 percent less likely to die (strength ratio). risk of 0.75). And, perhaps most strikingly, those in the 10th percentile (bottom 10% of strength) were 27% more likely to die (33% for men!). And the thing to remember about the distribution of data is that there is no threshold of strength. The stronger you can stay, the less likely you are to succumb.

One of the problems with these types of studies is that they must sacrifice some level of control due to the large number of subjects. The researchers controlled for things like BMI, smoking status and other variables that could be measured. But they couldn’t control for things like genetic predispositions, access to quality health care, or other factors related to diet or physical activity that occurred in the 5 years between testing and monitoring. But given that these people were all over the age of 90, we could assume that some degree of resilience and healthy living was present. And while the actual percentages are slightly off due to confounding variables, the clear trend that strength benefits longevity is there.

The takeaway here is that the best day to start strength training was 20 years ago. If you missed that one, the next best day is today. There are many factors that go into health and longevity, and being strong is certainly one of them.