Studies of have shown that the discs in your spine are swollen up to twice the normal size when you first wake up in the morning.  With light activity, the swelling reduces after about 2 hours.  Before you set your alarm clock next Saturday morning before that tournament, consider adding those 2 hours to help your back reach its peak potential:
 
Wake up at 6am
Light walk, breakfast, stretching, light jog 6am-8am
Start practice on the table 8am
First tournament match 9am
 
In order to get the proper amount of rest, try to go to bed by 10pm to ensure 8 hours of sleep.  If your normal sleep pattern doesn’t allow you to go to bed early, then consider adjusting your sleep pattern about 1-2 weeks before the tournament to ensure plenty of rest.
 
Studies of have shown that 85% of Americans will have back problems at some point in their lives.  If you play table tennis at a high level, the chances are about 100% that you will have problems at some point…  due to the fast rotation and sometimes awkward movements involved in table tennis.
 
So besides waking up early, what else can you do to avoid having back problems?
#1 Perform core and back strengthening exercises on a regular basis.  With a stronger core and back, you are less likely to get injured.
#2 Warm-up before every practice with light jogging, bike, stairs, or other light cardio workout for 15-20 minutes.
#3 Put on your tracksuit during every break to keep you muscles warm.
#4 Be consistent at stretching after practice and tournaments.  You might feel like jumping in your car and driving home immediately after practice.  But if you are disciplined in your stretching today, you will be able to avoid most injuries tomorrow.
#5 Change your clothes.  After a hard practice, put on dry clothes before heading to dinner.  Sitting for hours in wet clothes will tighten your muscles.
#6 Listen to your body.  If you body needs more warm-up, then do more warm-up.  If your back locks up during a practice session and you cannot continue, then don’t continue. 
 
Keeping your back in good shape is one of the best ways to prevent injuries and also one of the best ways to add power to your game.  Spend disciplined time on your preparation, warm-up, stretching, strengthening, and cool down and you will be well on your way to an elite level.