One of the hardest parts about exercise prescription is knowing exactly what weight and how many repetitions to prescribe. Exercise prescription is not a shot in the dark! There is a way to determine how to prescribe the exercise to give the best benefit. Below is a technique described that is research based that we utilize in our practice at IDEALFIT.
The use of ERF (or estimated-repetitions-to-failure) is based on many studies. One study published in the Journal of Strength and Conditioning in 2017 of 81 subjects ages 18-60 years old showed the best benefits came from training at moderate to heavy loads. These subjects completed exercises (chest press and leg press specifically) based on protocol to estimated failure and then exercise reps and weight were adjusted accordingly.
The big takeaway here is that training at very light weights (therabands and tiny dumbbells) is not likely to improve your fitness, maintain your function, or decrease your pain. Moderate to heavy loads do this. This applies to young and old!
Deciding what a moderate-heavy load for you may be a daunting task, especially when overcoming injury. Even more reason to work with a Physical Therapist that will help you get the correct exercise weight and repetition prescription!
Leah Kluemper, PTA