什麼是訓練負荷？急性與慢性負荷解析

Training load is a measure of the total physical stress a workout or a block of training places on your body, combining how much you did (duration, distance, or volume) with how hard you did it (intensity or effort). It is most useful tracked over time as two numbers: acute load, a short-term rolling average (commonly 7 days) showing recent stress, and chronic load, a longer rolling average (commonly 28 days) showing your established baseline of fitness and tolerance.

The acute:chronic workload ratio, or ACWR, is acute training load (your recent 7-day average) divided by chronic training load (your 28-day average), and it shows whether your current training is spiking above, matching, or falling below what your body has recently adapted to. An ACWR of 1.0 means this week matches your normal training pattern; values meaningfully above 1.0 mean load is ramping up faster than your body has adapted to.

Sports science research generally places the lower-risk ACWR range between about 0.8 and 1.3, with injury risk rising as the ratio climbs past 1.5, meaning acute load is roughly 50 percent higher than your recent chronic baseline. A ratio well below 0.8 is not inherently dangerous but usually signals detraining or a very light week rather than an injury flag.

The most common method is session RPE load: multiply the session's duration in minutes by your rate of perceived exertion on a 0-10 scale, so a 45-minute session at an RPE of 7 produces a load of 315. Strength-focused training often uses volume load instead, sets multiplied by reps multiplied by weight, and endurance training may use TRIMP or a pace-and-heart-rate-based formula, but all three feed the same acute and chronic rolling averages.

The acute:chronic ratio itself, roughly 0.8 to 1.3 as a lower-risk band, holds across age and sex because it is a relative measure of your own recent training against your own baseline, not an absolute number compared to other people. What differs is chronic load's typical size and how fast it is safe to raise it: general population and older adults usually build chronic load in smaller increments and need more recovery days between load spikes, while trained younger athletes and those training for hypertrophy or endurance events can sustain a higher absolute chronic load and tolerate slightly faster ramps, provided sleep and recovery markers stay steady.