Active vs passive recovery — what the evidence actually says

"Rest is when you do nothing." That's what half of amateur athletes believe. The other half believes the exact opposite: "rest is when I do something light because otherwise I'll get rusty." Neither is right. The truth is less neat and more useful.

The two categories

Passive recovery: no structured physical activity. You walk normally during the day, you don't train. Sleep, food, hydration.

Active recovery: very low-intensity activity — HR below 65% max, RPE 2-3 out of 10, fully conversational. Typical examples: easy jog, flat cycling, easy swim, yoga, walking. Duration 20-60 minutes.

What physiology says

After a hard session, your body is repairing muscle microdamage, restoring glycogen, normalizing hormones, and clearing metabolites. Two key questions:

### 1. Does light activity speed up or delay recovery?

It accelerates the first minutes, modestly. It increases blood flow, helps clear lactate (which is actually already gone within a few hours — that's not the real bottleneck). It doesn't affect muscle microdamage repair, which takes 24-72h regardless of what you do.

### 2. Does light activity interfere with adaptation?

Only if you push the intensity. If you stay in Z1 (RPE 2-3), it doesn't interfere — and may actually amplify cardiovascular adaptation (more Z1 volume = more capillarization). If you drift into high Z2 or Z3, you're training, not recovering, and you stack fatigue on the system without giving it a new stimulus.

When active wins

Day after a quality session (intervals, tempo, long run): 30-45 min of Z1 jogging helps. Wakes you up, moves the system, doesn't stress it.

Mid-week of a high-load block: when you're doing 3-4 hard sessions in a week, the days in between are active recovery.

Pre-race day (-1 or -2): 20-30 min easy with 2-3 short strides. Wakes the system without fatiguing it.

When passive wins

Day after a long race or ultra: your body is repairing significant damage. Adding light volume gives nothing back; it takes away recovery.

Symptoms of excess fatigue: insomnia, resting HR +10 bpm, low motivation, lingering soreness. Passive for 24-48h.

Incipient illness: if you feel "off," scratchy throat, take the passive day. Pushing leads to a week off instead of one day.

Minor injury: when there's real pain (not just discomfort), passive.

The "easy day that turned into a hard one" mistake

Classic mistake of the motivated amateur: heads out for "30 min easy Z1" and ends up doing 50 min of mid-Z2 because "the pace felt good." That's not recovery — that's a low-quality workout that ate your recovery for the day. If you're going to do active recovery, set a hard cap: 30 min, HR under 130, walk the last 5 minutes.

What actually moves the needle, on top of activity

Beyond active vs passive, here's what matters:

1. Sleep: 8+ hours the night after a hard session. Non-negotiable.

2. Protein: 0.3-0.4 g/kg of protein within 2 hours post-session. ~25-30 g if you weigh 70 kg.

3. Carbs: replenish glycogen with 1-1.2 g/kg/h for the first 4h after a long session.

4. Hydration: replace 125% of fluid lost (measure pre/post weight if you want to be precise).

5. Compression: compression socks are modestly useful, especially for heavy legs. The evidence is mixed but the cost is low and many athletes prefer them.

6. Post-workout cold: ice bath or cold shower 10 min reduces perceived soreness. Caveat: if you're in a strength adaptation block, cold reduces the adaptation. Skip post-lifting.

7. Foam roller / massage: reduces perceived DOMS. The physiological adaptation doesn't change, but you feel better.

What does NOT meaningfully help: static stretching post-workout, "eat carbs at 8 PM or they go to waste," electrostimulation, BCAA supplements if your diet has enough protein.

How Vetta handles it

Vetta computes required recovery with [this public calculator](https://vettatrainer.com/herramientas/recuperacion) that takes the last session's TSS + your CTL + sport. It returns suggested recovery days. In the auto-generated week, those days are programmed as active or passive depending on accumulated fatigue (TSB) and the next hard session.

Useful summary

Day after quality: active (easy jog 30 min Z1).

Day after long run: passive or very active (walk, yoga).

Day after race: passive 1-2 days.

Day before race: active short + strides.

Accumulated fatigue or bad sleep: passive, you recover more.

[Calculate your recovery days here](https://vettatrainer.com/herramientas/recuperacion).