First, I would like to address proper massage.  What is a proper massage?  I am not talking about a day at the spa, though I like to indulge myself.  A proper massage would be performed by a licensed massage therapist you trust.  One who has proper training and continued education as well as experience with athletes.  It is also important that the massage therapist have experience with various sport injuries. 
 
Secondly, I would like to address what happens to our bodies after 30 years of age, having one of these bodies myself.  I will keep it simple, as there are many physiological changes as we age.  Simply put, we lose flexibility and become stiffer.  We tend to get tired more easily.  It takes us longer to recover; we do not bounce back as quickly.  Due to this, we injure more easily and take longer to heal. 
 
Now, let us get to the heart of it.  Why is massage therapy important for athletes? 

I have the opportunity to work on a starting baseball pitcher in MLB who had never had a surgery or debilitating injury that took him out of the game.  What was his secret?  In addition to stretching during season, he diligently receives massage therapy after most games he pitches.  He is just 31 years of age, so time will continue to tell if the formula works for him.  My theory is that continued massage will serve him well.  Compared to many of his colleagues the same age or younger, who were not receiving massage as part of their recovery regimen; many had received surgeries that take a considerable time to recover from, hence taking them out of the game or even their career.  In contrast to this, I have also worked on an outfielder who has been in the game for nearly 20 years, placing him in the over 30 years of age category, and hardly ever stretches or receives massage therapy.  Unfortunately, he has received many surgeries and debilitating injuries taking him out of the game and enduring long recoveries.  Receiving massage therapy is sounding better already!
 
Massage therapy is a great addition to the athlete over 30 years of age.  Though the benefits of massage are plenty, for the 30+ athletes, I would narrow it down to the two top reasons I have seen in my 9 years experience.  Massage therapy for athletes over 30 years of age is important for optimal recovery and prevention of injury. 
 
For optimal recovery time, massage therapy should be performed if not immediately then 24-48 hours after intense training or performance event.  Massage promotes waste (lactic acid) out of the muscle tissue, which will also decrease muscle cramping.  Having massage will decrease delayed onset muscle soreness (DOMS).  In essence, massage helps to repair damaged tissue and help to resume training quicker. 
 
Massage therapy for the over 30 athlete is necessary in prevention of injury.  Regular massage from a therapist you trust with proper training and experience can help to identify areas of tension before injury occurs.  You can work with the therapist to help address issues that arise during training and to help avoid chronic strain in typically trained areas.  Essentially increasing flexibility, this leads to less stiffness and less injury.  Stretching is also a great way to recovery and prevents injury.  A skilled massage therapist can address these same areas on a deeper level in a more specific way. 
 
Massage therapy is not only important to the over 30 athlete, it is essential.  It is all about quality of life.  Whatever the athletic arena you are in be it running, tennis, golf or even baseball, massage will help you recover quicker and help prevent injury overall.  I see so many over 30 years of age athletes that have not been receiving massage therapy as part of their regimen.  They come to me with an injury, nearly ready to give up their sport.  If it is muscle, which it typically is, they can be back at the sport they enjoy even better than before.  Making them a believer, that massage therapy is an important part and not just a day at the spa.