What is Grip Strength

Before we discuss the link between grip strength and longevity it is important to define what we mean when discussing grip strength. Grip strength is the maximum amount of force production the hand can produce when making a fist.

Grip strength can be measured in numerous ways but is usually done through two ways. The first being more scientific and lab specific, where an individual will squeeze a grip testing device called a dynamometer, as hard as they can with their hands to test their strength. This will provide the maximal force production of the grip, giving a precise figure of grip strength. The other being a more accessible test, a max active hang test. The active hang test is much less precise and can often be a test of endurance rather than strength for more advanced individuals.

What is Longevity

Longevity is the length of time we live. In this case we will be discussing the relationship between grip strength and length of life (longevity).

Grip Strength as A Biomarker

Grip Strength and All Cause Mortality

There have been 3 meta analysis that have shown the positive association between weak grip strength and all cause mortality in the general population.

Grip Strength and Disease Specific Mortality

Poor grip strength has also shown a positive association with cardiovascular disease and cancer. In a study by Leong et al (1) they found that “grip strength was a more powerful predictor of cardiovascular mortality (hazard ratio 1.17) than systolic blood pressure”. This strength of relationship is surprising, that our ability to generate force with our hands and grip is more powerful than our blood pressure indicates how effective grip strength can be as a biomarker.

Although the data is very strong for cardiovascular disease, it is less conclusive for cancer. In a meta analysis by Garcia-Hermoso et al it was found that “higher level of muscular strength is not statistically associate with a lower risk of cancer mortality”. This shows us that grip strength is an important biomarker for longevity, however is less predictive of some causes of mortality like cancer.

Why Could Grip Strength Have This Relationship?

What is causing this relationship between grip strength and all cause mortality. It may not seem obvious at first, but there will be a clear relationship between grip strength and the activeness of our lifestyle. Elderly individuals who reduce their physical activity drastically will see large reductions in their grip strength. This reduction in physical activity is likely causing the increase in all cause mortality, not specifically the actual importance of having a strong grip.

Physical activity is essential as we age, especially as all our biomarkers are getting worse, our strength levels are decreasing, levels of muscle mass, our cardiovascular systems is worsening through a decreasing VO2 max and our bone mineral density is decreasing. If on top of this regression in physical capacity we are becoming less active then the decline will be dramatically faster.

Grip Strength Training Emphasis

Although it can be tempting to train grip strength once you understand it’s relationship with longevity, it doesn’t need that much specific training. When we understand the relationship between physical activity and grip strength and also understand the relationship between grip strength and all cause mortality we can make informed decisions about our resistance training. Physical activity causes grip strength, grip strength reduces the risk of all cause mortality. Once we understand that physical activity, strength training specifically, reduces all cause mortality, then we can create a specific plan for longevity that involves an active lifestyle and includes multiple strength training sessions per week. This may involve working on grip strength from time to time, but if your already doing pull ups, deadlift, rowing etc then I think you are already putting yourself in the best position for longevity. If a research study was to be done between max deadlift capacity and all cause mortality, it think we would see very similar results in terms of an association with improved all cause mortality, this wouldn’t mean the deadlift should be the number one emphasis of your training, just as grip strength shouldn’t be.

References