1. May help with faster recovery from injuries
Short Answer: Massage can help flush out inflammation and bring in red blood cells and nutrients while also keeping scar tissue from getting too tight, allowing an injured muscle to heal more quickly and with possible fewer complications.
More details: Injuries to muscles, tendons, and ligaments can be very frustrating, both because of the pain, but also because of the length of time that an athlete basically has to stop or ease up on their activities to allow for healing. So the faster an injury can heal, the better. Not every injury can be helped by massage (such as a broken bone), so when recovering from an injury, it is important for an athlete to be in good communication with their doctor and be honest with their massage therapist to make sure that the form of massage being used will help the injury appropriately.
2. Increases flexibility
Short answer: Loosening muscles plus stretches integrated into massage strokes designed to lengthen muscle fibers can help increase flexibility, which may allow athletes to have a better range of motion, and will allow them to build more strength and power in their movements.
More details: Flexibility isn't just for dancers and gymnasts. The better a muscle moves and works, the more it will stretch. There are very few sports where loose muscles and more flexibility is a bad thing. The more flexible or a larger range of motion an athlete has, the easier it is for them to move, and it presents a larger range that they can use to build strength, which leads to being able to do movements more powerfully. Plus, a muscle that stretches more easily is less likely to get torn or ruptured by stretching too far during normal use.
3. May help prevent DOMS (Delayed Onset Muscle Soreness)
Short answer: Massage can flush lactic acid out of overworked muscles more quickly, plus the massage can soften over tight muscles and soft tissue which (along with proper stretching and hydration) can keep muscles from aching after hard usage.
More details: After a tough workout, practice, or performance, it can be tempting to just crash and not move. Unfortunately, that's when DOMS sets in. Delayed Onset Muscle Soreness is basically the muscles tightening up and getting very achy and painful after working out due to tight muscles and an accumulation of lactic acid, which is the natural byproduct of muscles working (basically, muscle waste - it's the stuff that gives you that burn-y feeling after lifting something heavy or working out after a long time off). Massage helps flush out this lactic acid so it hurts less after the hard work.
4. Helps muscles function better
Short answer: Massage helps move “good stuff in” and move “bad stuff out” so muscles can function in a healthy way, plus the manipulation of tissues and muscles during a massage gives them a workout of their own without having to exert the rest of the body.
More details: Athletes put a lot of stress on their bodies, so massage helps relieve some of that stress. It can help the muscles stay healthy and functioning properly, and can even help prevent injuries by keeping the muscles healthy and in good shape. Healthy muscles work better, help the athlete execute their sport better, and lets the athlete work to a high potential with less pain, which means less distraction and more focus on the sport, and a better mental recovery as well as a better physical recovery. Massage takes care of the muscles, mind, and body as a whole, and every athlete needs to have their whole body in top shape to achieve the best they can.