The universally accepted way to prescribe resistance training intensity is based on a percentage of one’s 1 repetition maximum (1RM). With this method of training prescription, the athlete must be tested on the their maximal strength for the selected exercises, then the coach can assign set and rep schemes based off of a percentage of the 1RM.
Though this method is effective and has certainly stood the test of time, it does have several limitations. First, 1RM testing can be time consuming and dangerous. Second, throughout a training cycle, 1RM will likely change, and thus require frequent testing. Third, different athletes can tolerate different rep schemes at a given 1RM, and therefore standardized training programs may not be appropriate for all athletes. Moreover, an athlete’s strength potential can fluctuate significantly on a day to day basis based on recovery status, hydration, readiness, etc.
Other means of prescribing resistance training intensities have been developed. For example, (and discussed in previous blogs) velocity based training provides a novel and effective way to prescribe weights. However, one requires the appropriate technology (e.g., linear position transducer). A simpler method of guiding resistance training prescription is through the use of ratings of perceived exertion based on a “reps in reserve scale”. This system was popularized by elite level Powerlifter and coach, Mike Tuchscherer of Reactive Training Systems.
This system essentially has the lifter rate a work-set on a 10-point scale corresponding to the number of reps left in the tank. See the table below for a general overview of the scale:
|RPE||Reps in Reserve|
A new study published ahead of print in the Journal of Strength and Conditioning Research evaluated the efficacy of this “RPE/RIR” method. The researchers tested squat 1RM’s in well trained and novice lifters. Following the 1RM, subjects performed singles at 60, 75 and 90%. Bar velocity was measured at each set for all subjects with a Tendo unit.
The results showed that at 90 and 100% of 1RM, the experienced lifters demonstrated lower mean velocities. The authors suggest that this is because novice lifters are unable to lift maximally due to inefficient recruitment and potential inhibition for the golgi tendon. This also likely explains why RPE’s on the 1RM attempt were near 10 (9.8) for the experienced group and only 8.9 for the novice group. Additionally, there was a strong negative correlative between RPE and bar velocity at all percentages (r=-0.88).
The authors conclude that RPE based resistance training using the “reps in reserve” concept is a practical and efficient way to prescribe training intensities in athletes. This system is adaptable to daily fluctuation in strength, accommodates lifters of different abilities and doesn’t require 1RM testing to be used.
Zourdos, M. C., Klemp, A., Dolan, C., Quiles, J. M., Schau, K. A., Jo, E., … & Blanco, R. (2015). Novel Resistance Training-Specific RPE Scale Measuring Repetitions in Reserve. Journal of Strength and Conditioning Research, Ahead of print. .