Out of the many routines to make time for each week, stretching is the one most likely to fall by the wayside.

But it might be why your neck muscles are tense or your back hurts by the end of a long workweek. Or maybe it's why you're feeling stiffness in your knees after a workout.

"Regularly stretching certainly comes with benefits, mostly because it builds flexibility and preventive measures," says Dr. Alysia Robichau, a sports medicine doctor at Houston Methodist.

Why is stretching important?

Most people don't think to stretch until something aches, but here are five reasons to proactively make time for stretching on a regular basis:

1. Increased range of motion

Stretching lengthens your muscles.

"As you continue to stretch, you become more flexible, able to reach or extend farther," says Dr. Robichau.

This increased flexibility helps improve the range of motion in your joints, including your neck, shoulders, hips, knees and more. Taking steps to stay limber and mobile makes performing everyday tasks and the activities you enjoy easier.

2. Preventing aches and pains

"Stretching also calms your muscles and helps keep them strong and healthy," says Dr. Robichau.

Having muscles that are strong and flexible encourages optimal use, like holding proper posture while sitting all day or lifting a heavy item correctly. It also reduces the chance of those all-too-common aches and pains, like a sore neck or back.

(Related: How to Improve Neck Pain)

3. Reduced risk of overuse injuries

Your muscles get tight as you work them.

"Tight muscles don't perform as well as long, flexible ones, and they're definitely at higher risk for injury," Dr. Robichau explains.

This doesn't just apply to exercise-induced injuries. People who perform repetitive movements or do a lot of heavy lifting, pushing or pulling as part of their job should make time to stretch after a long workday, notes Dr. Robichau.

"Is stretching guaranteed to prevent pain and injury?" asks Dr. Robichau. "No. But it can certainly help to reduce the risk."

4. Improved performance

It's easy to see how your physical performance can suffer as a result of stiff joints or tight muscles. (Related: Why Are Workouts So Hard Some Days?)

"Muscles work best when they're long and joints work best when they're flexible," explains Dr. Robichau. "A tight muscle won't have the same explosive power and an inflexible joint will have a more limited range of motion."

Improved performance also means better balance, necessary to stay mobile as we age.

5. Relaxation and stress relief

Dr. Robichau adds that stretching helps the mind focus, whether you do it following a workout or as a break in your busy workday.

In other words, it's a way to make time for mindfulness — being present and aware, concentrating on calm, positive and productive emotions.

"Ask yourself: 'What are my goals today? What do I want to achieve?' " recommends Dr. Robichau. "If you're stretching after a workout, those questions might instead be, 'What did I do well during that exercise? What could I improve for next time?' "

How to stretch correctly and safely

How long and how often do you need to stretch to reap the benefits of stretching? That's harder to answer. There's no defined regimen Dr. Robichau universally recommends for everyone.

"Stretching means different things for different people," Dr. Robichau adds. "It helps to start by knowing what you're stretching for."

For instance, a person who runs or lifts weights may only need to stretch for five to ten minutes after exercise to help prevent soreness in the muscles they worked; someone who wants to help calm everyday aches and pains may benefit most from a 30-minute, full-body stretch a few times a week.

Still, there are do's and don'ts that apply to anyone who's stretching:

DO make stretching part of your routine

"Stretching only now and again isn't enough," says Dr. Robichau. "It's best to make a plan for when you're going to stretch, how long you're going to stretch and which muscles you want to stretch — and then making that a part of your routine two or three times per week."

And know that it can take weeks to months to start seeing results.

"It's important to set goals for yourself so that you're staying on target and not just going through the motions," Dr. Robichau recommends. "For instance, set a goal that in the next two weeks you're going to extend your stretch farther or that the stretch becomes less uncomfortable — evidence that your muscles are becoming more limber."

DO hold stretches for at least 30 seconds

Just as stretching isn't really beneficial if you're only doing it now and then, stretching a muscle for five seconds and moving on isn't helpful either.

"Anything less than 30 seconds is likely fairly pointless," says Dr. Robichau. "With stretching, there's a good key point between 30 seconds and 60 seconds. You'll need to hold each stretch somewhere in this time frame to see a benefit."

DO stretch muscles critical for mobility

"A whole head-to-toe stretching routine could easily take 30 minutes or more," says Dr. Robichau. "Whether you make time for that or split muscles into different groups on different days depends on your goals."

The most important muscles for everyone to stretch regularly are the ones used most for balance and mobility, including:

• Neck muscles
• Shoulder muscles
• Biceps and triceps
• Lower back muscles
• Hip flexors
• Quadriceps and hamstring muscles
• Calves
  
  

(Related: 5 Muscles To Stretch To Improve Your Knee Health)

DO stretch after exercise

From foam rolling and massage guns to cryotherapy, there are all sorts of products and services aimed at preventing muscle soreness after a workout.

There's also stretching.

"The goal is to keep your muscles from getting tight so they can adequately repair," explains Dr. Robichau. "After a workout, a cool-down stretch calms your muscles, reducing blood flow and helping to decrease muscle soreness."

DON'T stretch cold

You may remember being told to stretch before gym class or playing sports. You may have also recently heard that stretching before exercise isn't recommended.

So ... which is it?

"What we know for sure is that stretching cold isn't beneficial," says Dr. Robichau.

But since stretching can generally help prepare your body for a workout, Dr. Robichau recommends engaging in some pre-stretch activity.

"I still say yes, stretch before exercise — but do a brief warm up first," Dr. Robichau recommends. "Maybe that's a set of squats, high knees, jumping jacks or windmills, then stretch for five minutes, then start your workout."

DON'T stretch toward pain

Will there be some discomfort when you first start stretching? Probably.

Should there be pain? No.

"If it hurts, you're not stretching anymore," says Dr. Robichau. "The pull on your muscles should be gentle, not sharp. Never push or pull to a point of pain."

DON'T bounce while you stretch

Workout routines of the past may have encouraged a stretch-bounce, stretch-bounce format, but Dr. Robichau doesn't recommend it.

"Not only is the bounce unnecessary, you can pull a muscle if you're bouncing while you stretch — defeating the entire purpose," Dr. Robichau warns.

DON'T stretch an injury without first speaking to your doctor

Movement and stretching can help an injury heal, but you need to be sure you're not exacerbating things.

"If you've torn a muscle or broken a bone, we may not want you to stretch for a while since it can pull against the initial healing process," Dr. Robichau explains. "Just as you wouldn't stretch the skin around an open cut or scrape, you don't want to open up an injury by stretching it."

When the time does come, your sports medicine doctor can help you understand how to adjust your stretching technique to limit significant stress on the injured area.