The image below is posted on the wall Queensland Academy of Sport Strength and Conditioning staff room. It’s a great example of movement efficiency, and the Strength and Conditioning team often referred to it when working with their athletes in the gym. For the purpose of this post, let’s call the boy lifting the box Jack (ie. Jack-and-the-box).
I’ve also seen similar images used for workplace manual handling (MH) training, to which I’ve often queried whether it’s appropriate.
With a young family I have watched the movement patterns of my kids and their peers over the years. I have noticed that the kids move in the same way when conducting a MH task similar to Jack. There is very little variance in technique between different kids.
In my workplace injury prevention role over the past three years I have used wearable technology and video analysis to conduct movement analysis of workers performing MH tasks in over 15 different industries. I’ve found that when adults are required to conduct a MH task similar to Jack, very rarely do they use the same technique, and vary rarely does the technique reflect the recommended MH training technique.
My (heavily physio and sports science influenced) thoughts are:
- After puberty, genetics and behaviour determines our strengths and weaknesses. Therefore as adults we tend to conduct MH tasks in a way that utilises our different strengths.
- As we get older, our connective tissue loses elasticity. Therefore the older we get, the harder it is to move into certain positions (…I struggle to get into Jack’s position at 41!)
- Injuries that we accumulate over the years change our movement patterns. Therefore adults conduct HM tasks in a way that protects or compensates for past injuries.
- Psych factors that tend to influence our behaviour as adults, such as complacency, laziness, stress, motivation etc.
Now, getting back to Jack. Is it appropriate for Strength and Conditioning experts use Jack’s image to help athletes with technique? One huge difference between workers conducting MH tasks and athletes training in the gym is the purpose of the task; athletes are generating maximal force to improve strength, workers and completing the MH task to get their job done. Therefore, it is a great image to demonstrate a position for athletes to use when they are required to generate maximal force.
So, is Jack’s image appropriate for manual handling training, or should we focus more on providing workers with the tools to identify their individual strengths and weaknesses, enabling them to modify their manual handling techniques accordingly?
The purpose of this post is not simply to voice my opinion from a physio / sports science perspective, but to generate a discussion.