03/18/2026
If you or someone you know is training through an injury, rebuilding strength after surgery, or just trying to get stronger the smart way, this is worth reading.
The American College of Sports Medicine just updated their resistance training guidelines for the first time in 17 years, and the biggest change affects how we measure intensity.
For years, coaches and trainers relied on percentages of your one-rep max. Now ACSM recommends focusing on Reps in Reserve (RIR): how many more quality reps could you do before you hit failure? That simple question replaces a lab test.
Why does this matter? Lower-weight training done with high effort (close to failure) builds strength and muscle just as well as the heavy stuff. That opens up options for everyone, regardless of age, pain level, or starting point.
For my patients recovering from ACL reconstruction, shoulder surgery, or managing knee pain, this validates what we've been doing clinically. You don't need to chase heavy weight to get strong. You need to chase effort.
The fundamentals haven't changed. The measurement just caught up.