Strength athlete here, I train in the evenings and my quality of sleep is always garbage when I'm peaking from all of the stress on my CNS. The end of cycles are hands down my worst sleep weeks, I'll be dog ass tired and have trouble staying asleep.
For one person a heavy day might be a few sets of deadlifts at 80-90% 1rm, for some of us that might mean 2-2.5 hours of training where are warm up alone moves considerably more mass than your entire training and then we also tack on multiple accessory movements and conditioning and if you aren't doing that in the morning it's almost certainly going to mess with your sleep quality that night.
I have a training-induced insomnia blog post that is years old and gets hits every single day without fail. It's probably 1/4 of the total traffic on my personal blog and probably more like 60-65% of Google-referred traffic despite the fact I have 18 years of blog posts.
For one person a heavy day might be a few sets of deadlifts at 80-90% 1rm, for some of us that might mean 2-2.5 hours of training where are warm up alone moves considerably more mass than your entire training and then we also tack on multiple accessory movements and conditioning and if you aren't doing that in the morning it's almost certainly going to mess with your sleep quality that night.
I have a training-induced insomnia blog post that is years old and gets hits every single day without fail. It's probably 1/4 of the total traffic on my personal blog and probably more like 60-65% of Google-referred traffic despite the fact I have 18 years of blog posts.