Recovery tools (foam rollers, massage guns, ice baths, compression boots, supplements) have minor effects. Sleep is the single highest-leverage recovery intervention by a wide margin. Most fitness plateaus are sleep problems wearing other costumes.
What sleep actually does for fitness
Growth hormone release peaks during deep sleep. Muscle protein synthesis runs overnight. Glycogen replenishment. Hormonal recovery (cortisol drops, testosterone and other anabolic hormones recover). All sub-optimal in sleep-deprived states.
Sleep practices that improve fitness
7-9 hour target. Same bedtime and wake time within 30 minutes. Cool bedroom (17-18°C). No screens 30 minutes before bed. Caffeine cutoff by early afternoon. Alcohol limits (alcohol degrades sleep quality measurably).
If you've optimised training, nutrition, and supplements but plateau persists, the lever is usually sleep. It's free and unsexy but works better than any expensive recovery tool.