Jump Performance Decline During an Off-Season Block

A drop from 42.1 to 39.8 cm is about 5.5%, which is larger than typical day-to-day jump-mat variability in a familiar test. At the same time, weekly session-RPE load increased roughly 29%, sleep is short at 6.2 hours, and knee soreness has appeared. The most likely explanation is accumulated fatigue or early non-functional overreaching rather than a true training plateau. The coach's interpretation-that jump performance has stalled because volume is insufficient-is not supported; adding plyometric volume would likely deepen the fatigue. Before changing the program, rule out testing error: same mat, same warm-up, same countermovement technique, and same time of day. Check whether the team tested after a hard session or after poor sleep, and confirm no athlete is jumping in different footwear. Because there is no force plate, do not overinterpret small changes in a single week; use the weekly average and individual readiness data. Also screen for illness and menstrual-cycle phase only if you have reliable tracking, and do not treat soreness as a diagnosis. The practical conclusion is to hold or reduce load, not add plyometrics.

I would cut plyometric volume by about 40-50% for the week-for example, from three sessions to one or two low-volume sessions of 40-60 ground contacts-and keep the remaining jumps low-intensity (pogo hops, low box step-offs, submaximal CMJ) rather than maximal depth jumps. Strength training can retain intensity but should reduce volume: keep the main lifts at roughly 80-85% of estimated 1RM for 2-3 sets of 3-5 reps, and remove back-off sets or high-rep accessory work that adds fatigue without a clear return. The goal is to preserve neuromuscular qualities while allowing recovery before testing. I would use readiness scores to autoregulate: if readiness is low or knee soreness exceeds 3/10, substitute a low-impact session. Sleep and nutrition should be addressed directly because 6.2 hours is below the team's likely need. I would not add a fourth plyometric session. This plan is based on the mismatch between the coach's desired stimulus and the data showing fatigue, not on a generic deload template.

I would reintroduce high plyometric volume only when three conditions are met: CMJ is back within about 2-3% of the athlete's baseline (roughly 41-43 cm for this group), readiness scores are stable for at least three to five days, and knee soreness is absent or no more than 1/10 during and after sessions. I would also check landing quality and takeoff symmetry visually, because a jump mat can hide altered mechanics. Track weekly CMJ average, session-RPE load, sleep hours, soreness, and readiness. After reintroduction, increase ground contacts by roughly 10-20% per week rather than jumping back to three full sessions. If CMJ falls again by more than about 3% while load is rising, that is a signal to hold volume rather than push through. Testing day itself should be treated as a high-output session, so the following week should not immediately return to the previous plyometric volume. This criterion-based approach prevents using a single good or bad testing day as the sole decision point.