Personally I train in the morning. KNOW THIS: first thing in the morning we are up to 19mm taller in the seated position compared to the evening. This is due to the fact that during the night the disks between the vertebra in our spines become more hydrated with fluids. You literally are taller in the morning than when you go to bed at night. During the day we lose this liquid from or disks, in fact 90% of it is lost 60-90 minutes after getting out of bed.
Here’s how you can decide – if you perform a flexion movement of the torso (lean forward; touch fingers to the floor) as you get out of bed in the morning you will put up to 300% more pressure/compression on your disks. This can be disastrous for someone suffering from back problems. UNLESS you bend over and maintain a neutral spine.
People suffering from back problems should keep there backs in the “neutral spine” position as much as possible and avoid flexion and flexion with rotation of the torso, especially just after getting out of bed. Wait 60 – 90 minutes if you can’t bend without a neutral spine.
90% of back pain comes from muscle weaknesses and imbalances.