2 questions:
- when showering using warm water and finishing off with ice cold, will the cold water stun/stock hair growth or enhance it?
- Can pimples where one has had a transplant be popped?
- No, but I suspect it would stun / or shock your body. It will not contribute to hair growth, though.
- Yes, but use care. Warm compresses will speed up the process. See Scalp Pimples Weeks After Hair Transplants for more.
Hot water drys hair and can cause damage. Luke warm water opens the hair follicles which is good when your deep conditioning, cold/cool water seals the follicles which helps lock in moisture. Follow with a sealant like oil or shea butter to provide further moisture and protection.