Massage - the scientific and systematic manipulation of soft tissue. The "scientific" basis for massage therapy is anatomy and physiology.  "Systematic" refer to the treatment routine of the individual therapist. Anatomy is concerned with the location and functioning of the body's bones and muscles. Physiology is the body's biology and chemistry.

What other health practices are most closely associated with therapeutic massage?

Chiropractic (90%) and physical therapy (10%). Chiropractic is concerned with the correct alignment of the spinal column to allow the unimpeded flow of nervous system signals through the body.  Most commonly spinal misalignment results from trauma, such as accident, fall, break, or fracture. In rare cases, severe muscle tightness, hyper tonic contraction will pull hard tissue, bones, our of proper alignment.   Someone seeing a chiropractor should see a good massage therapist just before their chiropractic visit. The Chiropractor's adjustments will take effect more easily and will last longer if this advice is followed.  Otherwise, after the chiropractor's adjustment, hyper tonic muscles will act like big elastic bands and slowly pull the bones out of adjustment.  This is the traditional "knock" on chiropractors, "Once you start seeing a chiropractor, you never stop." A good chiropractor will advise his client to see a good massage therapist, or may even have a massage therapist on staff.  A good massage therapist will probably not stay long with a chiropractor due to the limited scope of the massage practice.  Physical therapy is designed to restore proper functioning of the body after injury.

Pain is the bodies warning system. If it hurts there is a reason for it. If it's a tissue issue, massage therapy is the answer.  Not responding to pain usually results in more pain, until it gets painful enough to seek help.  The longer the hurt persists, the longer it will take to heal.

Recruitment refers to either the healing process (positive) or the spreading of pain process (negative).  When muscle tissue is hypertonic, locked in an involuntary spasm, the remaining muscle tissue, not in spasm, and the surrounding synergists, will get invoked trying to bring relief and functionality to the injured tissue.  Hypertonic tissue does not get properly irrigated with blood, water, and nourishment. Massage opens up tissue allowing healthy irrigation and the removal of water products.  At the mechanical level, when a prime mover (muscle) is not operating at its expected level, the surrounding synergists will be invoked dysfunctionally thus causing them to become irritated. This is how untreated pain spreads.  This is negative recruitment. Positive recruitment refers to the continued treatment of the tissue surrounding the injured tissue in order to bring associative relief.

Tendons connect muscle to bones. There is an origin and insertion. The origin is usually the more stable or immobile end of the muscle.  The insertion is where a muscle goes to.  Muscles move in their contraction from insertion to origin.  Ligaments limit motion.  The difference between tendons and ligaments is muscle.  Both are avascular meaning low in blood supply thus longer to heal.

A spasm is an involuntary contraction of muscle tissue in order to protect itself "perceived" further injury, or overuse.  Spasm is akin to sabotage, a forced breakdown in functionality in order to obtain relief: rest, hydration, nourishment, waste removal.  A muscle will stay in spasm until it feels that it is "safe" for it to resume functioning.  "Perceived" refers to the innate intelligence built into muscle tissue.  A muscle is not ready to work unless it is relaxed.  A muscle 30% contracted has only 70$ of its functionality left to invoke.  The "burn" experienced by lifting heavy weights in the tearing of muscle fiber at a microscopic level.  The heals as scar tissue that while stronger than  the original uninjured muscle is no longer usable.