When to use ice/heat?
The rule of thumb with cold is if an area is red, swollen, inflamed or if it’s an acute injury, meaning an injury that just occurred, we want to cool the area down and prevent any inflammation. Its generally a typical anti-inflammatory that were putting on the patients skin or body part, wherever the injury occurred. / Heat will generally be used to prepare a body part or a portion of your arms or legs for exercise. It helps in increasing  blood flow or circulation, increasing tissue elasticity or flexibility, and it will just help warm-up or prepare the body to accept the exercise or the stretching that the therapist will be doing to the area.

Posture
Not maintaining good posture and adequate back support can add strain to muscles and put stress on the spine. Overtime, the stress of poor posture can change the anatomical characteristics of the spine, leading to the possibility of constricted blood vessels and nerves, as well as problems with muscles, discs, and joints.  All of the cam major contributors to back and neck pain, as well as headaches, fatigue, and possibly even concerns with major organs and breathing.

Proper lifting
Improper lifting technique can lead to back, leg and arm pain. Poor technique can cause both acute injury and serious chronic effects.
You must bend at the knees and left with them, Do not bend over and pick up something. Something as simple as picking up your newborn baby can trigger your back to spasm or and throw out a disc.