I was leafing through the November’s journal of strength and conditioning research this morning and read a piece by Alcaraz et al looking at the power-load curve in trained sprinters. It piqued my interest as I’d been looking at some jump squat power curves recently. Alcaraz et al used a smith machine and measured vertical bar velocity and ground reaction forces at 30, 45, 60, 70 and 80% 1RM using a half squat (90° knee angle) exercise in order to obtain peak power outputs in sprinters. Spoiler alert: peak power occurred at 60%. I like the concept of these profiles and have looked at various methodologies.
I’ve read studies looking at jump squats and testing profiles at % 1RM jump squat (not a test I’m too keen on), % 1RM back squat, % bodymass and selected loads. These use different methodologies including accelerometers, force plates, video cameras, bar trajectory, centre of mass trajectory, smith machines and squat racks. There are studies looking at cleans, power cleans, hang cleans, mid thigh cleans, pulls and snatch derivatives but nothing comparing them. That would be a complicated study design. So once you’ve narrowed that lot down and decided on something you can actually use as a measure, works with your athletes, that you have the contact time to implement, that works in increments it’s actually possible to load a bar in, you have your load-power curve. Sweet…so what now?
Do you train at that peak power? To the left? To the right? For how long? Sets and reps? That’s one exercise you have a load-power curve for, do you get it for multiple exercises? Suddenly that becomes a lot more testing, that’s going to impact on your contact and training time. You can’t really use it purely to prescribe training loads except for that one exercise, but you can use it to test the effects of your program design, you can see how each block has effected, if at all, that profile. For me I think that using squats is probably the best exercise for familiarity and ability to load it all along the force velocity curve and I have a myotest which makes it fairly easy to measure. It’s still something I’m playing around with at the moment but I’m looking forward to using the data.