Physical jobs produce tough people. It just makes sense - the harder the work, the harder the worker. Our popular culture is full of these images and stereotypes: burly woodworkers, strong mechanics, square-jawed miners, and more. It's kind of expected that tough jobs produce tough people, but this is just the conception, not the truth.
Jobs that require manual labour have always been understood as risk-factors when considering things like back pain and shoulder pain. Heavy manual handling, repetitive movement, and ongoing strain all place demands on the body that outstrip its ability to mend itself after exertion. But what about the benefits of exercise? If exercise is movement, and movement is healthy, then surely if you need to move for your job then you'd be healthier than the general population?
Exercise is the practice of exposing the body to a controlled amount of stress with the intention of strengthening it. Running, weightlifting, gymnastics and stretching all impose a controlled load on the body which, when adjusted over time, produce improvements in functional capacity. The key to this continued improvement is rest and down-time. When muscles work, they create waste, in the same way that the diesel engine on an eighteen-wheeler makes smoke when it works. This waste has to be removed, otherwise it may cause excessive inflammation, soreness, and wear-down. When muscles work, they undergo strain, in the same way that the driving chain of a bicycle experiences strain when turned by a pedalling cyclist. This strain needs to relax itself, otherwise it may cause muscles to tighten up and spasm painfully. When muscles work, they consume energy, in the same way that using a smart phone gradually drains the battery over time. If energy reserves are not replenished, then muscles cannot work as hard as they otherwise might be able to.
Removing cellular waste, relaxing fibrillar strain, and replenishing cellular energy reserves all require rest, and they all rely on different systems in the body that have a finite capacity. Just like muscles, the systems that sustain muscles can be strengthened as well, but only to a point and only if stressed correctly.
An athlete who exercises completes a program that takes a set amount of time and works towards a set goal. A construction worker starts work at 8, finishes at 5, and (in an ideal world) spends the time inbetween moving through different postures, lifting, bending, moving, and with little time at rest save for lunch breaks. Our athlete might work harder, but they work for a shorter period of time, and the result of this is that they have proportionally more time with which to rest. Our construction worker might not work up as much of a sweat as the athlete, but they work for a longer number of total hours, stress more systems in their body, and require more rest. Our athlete may train three days a week. Our construction worker is onsite from 9 to 5, five days out of seven. Forty hours a week. That takes a toll, and even for younger workers the strain of working in physical jobs can quickly outstrip the body's ability to replenish those empty reserves, both to repair the body as well as to help it function.
Heavy manual handling, awkward postures and lifting are all risk factors for workplace related muscular injuries. This is not just because a worker takes on strain when doing those tasks, but because when the worker's body isn't adequately rested, they are more at risk of injury. Fatigue affects workers as much as it affects machines, and sometimes going onto a jobsite when you're exhausted is about as safe as driving on a wet road with bald tires. So much literature is devoted to ergonomic positioning of desks, of creating safe job spaces, of good lifting strategies and of good handling postures, but so little of it concerns the importance of educating workers in active recovery strategies that can minimise the risk of work-related physical overloading.
So what does this mean?
Exercise and physical training are effective ways of improving overall health, but only when combined with a proportionally appropriate amount of rest. Too much or too little rest will decrease the effectiveness of the exercise that is done. People who sit at desk jobs for extended periods of time often have too little movement during their day. People who work on jobsites multiple days a week, people who handle heavy goods or people during their work, and people in manual trades often have too much movement in their day. Just because someone has a physically intense job, it doesn't mean that they're any more or less healthy than someone who doesn't.
So what can you do?
Construction workers, hospitality workers, care workers, nurses and even technical professionals like surgeons and dentists all need to incorporate recovery strategies into their working day to maximise the effect of downtime and minimise the overall strain imposed on their bodies by their jobs. This needs to be done outside of work hours; in an ideal world it would make more sense to spend four fifteen-minute blocks totalling an hour each day to run through some stretches and light movements to loosen up.
Talk to your physio about active recovery and rest strategies at work. Stretch, walk, and make the most of your down time.
See you in clinic.