Used to do the same with keto and fasting and definitely felt the energy was ‘missing’ in the gym. Tried getting in the gym earlier in the day to lessen the effect. I think I ended up trying to coordinate so I would have eaten on the workout day. Either way though, I found I would be either exhausted at the gym itself or later in the day (if I was fasting for the rest of the day). I reckon it was probably to with not taking in sufficient nutrients (setting myself up here) and should have taken some sort of supplement.
Joint issues
Coffee and creatine lads. Or speed.
Cut out booze and carbs?
Behave!
Trouble with your performance due to aging you say?
A lol for Zackster!
The cruelty on Dave today is absolutely off the chain!