The strength of your handshake could indicate how long you will live, according to scientists.
Other pointers to the length of your life are your usual walking speed, how long it takes you to get up from a chair and your capacity to balance on one leg.
As markers of physical health they are simple and cheap to measure. Now scientists have conducted a systematic review of research to assess the extent of their influence on the risk of death.
The findings are based on 33 studies from across the world, which included more than 50,000 men and women who were followed for up to 43 years.
The results show that people with a stronger hand grip and better performance on the other tasks lived substantially longer than their weaker counterparts.
Death rates were 67 per cent higher in people with the weakest grip strength compared with the strongest over the period of the studies, after taking age, sex and body size into account. Average grip strength declines with age and is around 27 kilos for a middle-aged woman and 40 kilos for a middle-aged man. One study showed a 3 per cent reduction in mortality for every kilo increase in grip strength.
Normal walking speed showed the strongest link, with a death rate almost three times higher among the slowest walkers. One study used a walking speed of one metre per second as the dividing line between slow and fast walkers.
Overall, from five studies including almost 15,000 participants, the researchers found the quarter who were the slowest walkers were 2.8 times more likely to die than the quarter who were the quickest.
Rising from a chair becomes increasingly difficult as people age, and the capacity to do so is a key factor in maintaining independence. Five studies involving 28,000 people found those who were slowest were almost twice as likely to die as those who were quickest.
The fourth measure of physical ability – the capacity to balance on one leg – was also linked with reduced mortality, but the studies were not conducted in comparable ways so the researchers were unable to calculate an overall figure for the reduction in the death rate.
Dr Rachel Cooper from the Medical Research Council's Unit for Lifelong Health and Ageing, who led the study published in the British Medical Journal, said: "Simple measures like these could help doctors identify those most vulnerable to poor health in later life and who may benefit from active intervention to keep them healthy for longer."
"But we need to identify clinically relevant cut off points for each measure in the same way that we have cut off points for Body Mass Index" [a BMI of 18-24 represents healthy weight, 25-29 overweight and 30-plus obese].
"These measures do appear to be useful predictors of current health and future mortality. They are incredibly simple and easy to record but despite their simplicity they are good markers [of longevity]," she added.
The four measures are related to a person's ability to perform everyday tasks, which is of increasing importance in an ageing population. They require strength, balance, muscle power, speed, motor control, mental concentration and adequate heart and lung function. These functions decline with age, contributing to increasing frailty.
All the studies were carried out on the general population, who were mostly elderly. In some people, poor performance on the measures could indicate underlying illness. But studies of grip strength and its link with mortality have been done on younger populations where the incidence of underlying sickness would be expected to be low.
The researchers say further work is needed to determine whether "a steep decline in physical capability may be a better predictor of mortality than is the absolute level at a single point in time".
People with the weakest grip had a 67 per cent increased risk of premature death compared with the strongest.
The slowest walkers were 2.8 times more likely to die than the fastest walkers.
Those who were slowest at getting out of a chair had almost twice the death rate of those who were quickest.
Capacity for sustained standing on one foot was linked with a lower death rate.