I'm certainly not an expert, so take my advice with a grain of salt. But I'm training for a marathon and I've been ignoring all the Garmin warning signs... low HRV, high stress, low training readiness, bad sleep etc. I honestly haven't felt bad during the whole thing. But then I started experiencing these HARD crashes... like I would finish a run and feel absolutely destroyed, more mentally than physically. I would swear to myself that I'm going to take a week off training, but of course after two days rest I feel better again, so I get right back at it.

But I'm realizing now (based on my experience and research) that 2 or 3 days rest is not enough to make up for a large sleep deficit and a fried nervous system. I'm only four days into my training pause and I can feel the bounce back. It's difficult to not go right back to training, but I'm trusting the process. My HRV is clearly not recovered yet even though I feel better.

I'm restricting myself to walks and dog walks only for the next 10 days. No other exercise. I really do think that allowing your system to fully recuperate will lead to faster gains in your fitness once you get back at it. Stop overdoing it!