How much sleep do I need to train?

Most adults do best on seven to nine hours. Under six for a week and the session will tell you.

Should I skip a 6am class if I slept badly?

One bad night: come, train lighter. A run of them: fix the sleep first and message Stevie.

Only if they change what you do. Most people know they went to bed at 1am without a watch telling them.

If the scales have stopped and the bar feels heavy, the first question at the consult is not about food. It is "how are you sleeping?"

Same wake time every day. Including Sunday. It anchors everything else.
Caffeine cut-off at 2pm. Earlier if you are doing the 6am classes.
Screens down 30 minutes before bed. The phone goes on charge in another room if it has to.
Cool, dark room. Blackout blind or an eye mask. Scottish summer light at 4am is a real problem.
Alcohol is not a sleep aid. It knocks you out and then wakes you at 3am. Two drinks costs a night's quality.
Eat earlier if evening training makes you wired. A proper meal after the 5:40pm class, then wind down.
Do not lie there. Awake for more than 20 minutes? Get up, dim light, boring book, back when sleepy.

The rules bend but do not break. Protect a fixed sleep window, black out the room in daytime, and read the shift-work guide for which sessions fit.

Loud snoring with pauses, falling asleep in the day, or weeks of insomnia are GP conversations, not coaching ones. Go.