What do I do before stretch training? After? How often should I do stretch exercises if I want to do splits? How long do I have to sit in the split if I train 3 days in a row with 1 day to rest?

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No slpits for me, thanks. I am told it is best to have 10 min. warm up before streching. I also like qigong with a built in warm up.

Before any type of exerciseing/split positions always stand, deep breaths and stretch arms up, have legs apart about 1ft, & lite stretch then after cpl mins strt ur splits; don't have to be long just till u feel the burn count to 3-5 & do again,mabye 5 reps to strt.
Do 3x a wk to strt..
Soon, you'll be doing the splits. I hope this helps ur splits. Good Luck..
And do safely, I'm rooting for you!!!✌☺

First thing first, always drink a glass of water. It wakes up your nervous system and lubricates your joints.

Second, meditate or visualize your day. You want to be calm before stretching. Stretching is more mental than physical. It’s a way to check in on yourself. Imagine stretching as your own personal yoga routine!

Third, do normal stretching before splits. I would look at a gymnastics warmup video. They have several ways they prepare for the splits and even split while standing up! Prior to doing the move. But make sure your overall routine is no longer than 10 minutes.