Once you put on your gi it's a whole new world. On the mats took away my worries you focus on technique and how to get better. first you warm up so you prevent injuries. Stretching is important since it helps with flexibility especially if you are limited. First you get instruction on how to execute moves form is important when learning jujitusu it's not about strength and muscle but finesse and reaction to every action.
If you get the technique down you don't need much torque when performing a submission or choke.
After the lesson you get time for free roll try to use the moves in your roll see if you could apply what you learned in your training make it feel natural. Sometimes you tap people and other times you get tapped. It's give and take doing jujitsu you learn and gain from the experience.
When you get a stripe you feel accomplished all your hard work paid off and you are constantly growing staying humble. That world carries over you become a better person and feel better about yourself.