The 'pain in the butt' could also be from the bowling... It's lower butt where attaches to leg (sciatic area) likely. When you don't tuck the tailbone during any physical actions, high chance of issues in this area. Do this: inhale, bring hands up the front of your body lightly touching the skin starting just below the navel/belly button, once reach the top of your head you should feel as if you stretched your chest and abdominal muscles, lengthening them upwards (which follows with the spine lengthening and opening). Feel like your head is lightly held as if by a string, then feel/notice your weight as it drops down the back. When it reaches the lower end of your rear/butt, you will notice the weight gets stuck/caught there. To release it into the legs: slightly tuck the tailbone forward. You will feel it drop to the knees: slightly 'press' them outward to feel the weight drop to the outsides of the feet. The adjustments to the feet are more subtle, but the main intention is to actively relax, (not limp), and adjust as needed until you no longer feel the strain in any part of your body, but instead you're allowing it to go into the ground. This intention needs to always be maintained in all actions in your life until you no longer need to pay attention to it, it just happens out of trained habit forming. If you do this, likely you'll be well with anything you do, not needing any correction of movements by your teacher to prevent detrimental effects from incorrect posture (although adjustments to movement for martial benefits etc.) will likely still be called for. Thanks.