Nearly 2 million people receive physical therapy every day, a number that's likely to increase as the population ages. For many, it can be overwhelming and intimidating. Here, three experts weigh in on what to expect, the keys to getting better and how to avoid "PT" in the first place.

When is physical therapy necessary?

"Most little aches and pains work themselves out in a day or two," said Dr. David Aiken, a rehabilitation specialist. "If within a week or so [the pain] hasn't resolved on its own or begins to affect your functionality, you should seek treatment."

Physical therapist Erin Ball said many people make the mistake of waiting to seek treatment, hoping that the pain will go away. "The trouble is that certain injuries get worse with time. An easy fix now could be a very complicated fix down the road."

The assessment

Most PT begins with a thorough assessment, said physical therapist Nabila Tanas. She delves into the patient's medical history, looking for underlying causes. She also educates the patient about how lifestyle changes may help.

The treatment

Most therapy consists of multiple techniques, said Aiken, including therapeutic exercises to restore strength and function, as well as manual therapy, which is a "detailed massage" designed to soothe soft tissue and loosen joints and muscles.

Tanas specializes in the manipulation of muscles and soft tissue to help relieve pain, either locally or elsewhere on the body along nerve pathways. For instance, if a patient is suffering from chronic headaches, the problem may stem from stiff muscles in the neck or back.

Common mistakes

Most PT requires patients to do exercises on their own. Experts agree this key component of treatment is also the most neglected, which can delay healing.

To keep his patients motivated, Aiken said, he stresses the correlation between the exercises and the outcome.

"They know if they do the exercises, not only will they feel better, but they'll be able to do things like play catch with their kids or get through a workday without hurting," he said.

Another common PT patient mistake is not keeping appointments with the therapist, Tanas said. "You have to stick with a routine — usually a few times a week," she said. PT "is not something you can do sporadically."

It's also important to be honest with the therapist, Ball said. "If you have a lot of job and family responsibilities, be upfront about what is reasonable with your schedule — say one treatment a week vs. three."

What if I'm not getting better?

An important part of PT is continually reassessing a patient's progress, Ball said. "At every appointment we ask what's working and what isn't. This open dialogue provides an opportunity for therapist and patient to go back to the drawing board if necessary. By using a patient's feedback you can always adjust to make sure you're on the right path."

Is PT inevitable?

Regardless of how well we take care of ourselves, over time the body starts to break down and injuries are more likely. But there's a lot you can do to stay healthy. Ball said a fit lifestyle pays big dividends later in life.

"Everything from our sleeping habits, stress management and level of activity is very important as we get older," Ball said. "Being proactive is crucial to maintaining a high quality of life."

Said Aiken: "If people work on their mobility and muscle strength, they can still be active well into their 70s and 80s."

Billing issues

Most health insurance limits how many PT sessions you can have. Insurance companies may also want to verify if you require PT as the result of an on-the-job injury that either workers' compensation or legal action could pay for, especially if the injury was caused by an accident.

PT is often more costly at hospitals compared with other practices. Even if you receive therapy on an outpatient basis from a hospital-affiliated practice, you may be billed at a higher rate than at other practices. Try to find out the billing rate the practice will charge.