There are, contrary to what many insta-trainers will tell you, a finite number of tried and tested exercises that improve your strength and conditioning. Don’t get us wrong, there are hundreds of movements possible but most are simple changes to the same joint actions across the board. Many people fall into the trap of doing the same few exercises over and over again and eventually stagnate, get bored or get injured. We don’t think that should ever happen and here’s why.
Centre of mass (COM) refers to the part of you that is the middle and heaviest point – literally the centre of your mass. When you hold a heavy object, the position of that object changes where your (now joint) COM is. This requires us to change how we use our muscles to balance and stabilise. The further the object from our own COM the more of a challenge this becomes. We have the option to hold things; centrally, behind us, in front of us, on one side or down to our sides. Each of these options will influence to some degree the difficulty of the exercise performed.
A simple practical example is seen above – take a kettlebell you find heavy and hold it down by your side to do a split squat. The same kettlebell held at your chest with both hands will not pull you sideways (like the weight by your side does), but instead forwards. With the side position we resist sideways flexion, whilst with the front example we resist forwards flexion. In both cases we are split squatting with the same weight so our legs are essentially doing the same amount of work.
Harder or easier?
Some positions will lend themselves to holding more weight than others. Our grip may tire using heavy dumbbells by our sides but on our shoulders our torso may tire first. Each person will have different strengths and weaknesses but in general the rules of physics apply:
lower COM is easier to balance
placing weight to one side or the other will be more challenging for your torso than having a balanced load each side
loads on our front will be harder to work with than loads directly on our shoulders (or upper back)
If you’ve been finding yourself lifting the same weights over and over and aren’t seeing the results you want, consider changing the way in which you use loads. Try the same weight with a different bit of equipment, or use one heavier weight instead of two lighter ones. The possibilities are (almost) endless!