Autoregulate the session
Warm up and see what the bar feels like. If a normal weight feels heavy, keep the load but do fewer reps and fewer sets. Training by feel beats forcing a planned session when you are wrecked.
Keep training but cut volume and go by feel; hold intensity on main lifts, drop the junk accessory sets.
One or two bad nights will not tank your gains, so still train, just scale it. Autoregulate: keep your main lifts near their usual weight but stop each set 1 to 2 reps further from failure, and trim total sets by 20 to 30 percent. Poor sleep raises perceived effort and hurts coordination, so skip risky max attempts.
Warm up and see what the bar feels like. If a normal weight feels heavy, keep the load but do fewer reps and fewer sets. Training by feel beats forcing a planned session when you are wrecked.
Keep the big compound movements that drive progress, and drop the low-value accessory sets. Doing half your normal volume hard still maintains muscle far better than skipping entirely.
Sleep loss slows reaction time and coordination and inflates how hard everything feels, so this is not the day for a PR attempt or grinding singles. Save intensity records for a rested day.
If bad sleep drags on for weeks alongside low mood, exhaustion or poor recovery, talk to a doctor rather than just pushing through.
Keep training but cut volume and go by feel; hold intensity on main lifts, drop the junk accessory sets.