Reps in Reserve (RIR) refers to the number of repetitions you could still perform at the end of a set before reaching muscle failure. For example, if you finish a set and feel you could do two more reps with good form, your RIR is 2. This concept helps manage training intensity and fatigue, which can directly influence your daily energy levels.
When you train with a low RIR, meaning you push close to failure, your muscles experience more fatigue. This can lead to greater short-term tiredness and slower recovery, which might reduce your energy for the rest of the day or for subsequent workouts. On the other hand, leaving some reps in reserve (higher RIR) allows you to train effectively while minimizing excessive fatigue. This approach helps maintain higher energy levels throughout the day because your body is not overly taxed by the workout[1].
Using RIR to guide your training intensity also supports better recovery. Training to failure frequently can cause more muscle damage and central nervous system fatigue, making you feel drained. By stopping a set a few reps before failure, you reduce this strain, allowing you to feel fresher and more energetic on a daily basis. This method also enables you to train more consistently over time without burnout or injury[1].
In practical terms, if you aim to keep 1 to 3 reps in reserve during compound lifts, you can maintain good training volume and intensity without excessive fatigue. This balance helps you stay energized not only during your workout but also in your daily activities. It also means you can perform better in your next training session, as your body has had enough time and energy to recover[1].
In summary, managing your reps in reserve is a useful strategy to control fatigue and preserve daily energy levels. It allows you to train hard enough to make progress while avoiding the exhaustion that comes from pushing every set to failure.
Sources
https://rippedbody.com/rpe/
https://www.cleaneatzkitchen.com/a/blog/gym-talk-a-glossary
