A soft tissue injury is a strain or tear in a muscle, a tendon (the tissue that connects muscle to bone), or another tissue that supports your joints. A hamstring or calf strain is one example. A soft tissue injury does not involve a broken bone.

Returning to running after a soft tissue injury involves slowly rebuilding the injured tissue's ability to handle running again. The goal is to protect the healing tissue while keeping up your strength and fitness.

Your doctor, physical therapist (a specialist who helps you move better and get stronger), or athletic trainer will help you decide when it's okay to start running again. This is especially important if your injury was serious or keeps coming back.

Before you start running again, your doctor or rehab team may check:

• Your strength in the injured muscle or area.
• How much pain you have during movements that are like running.
• Whether you have swelling after an activity.
• How far you can move a joint or muscle. This is called range of motion.
• Your overall fitness level.

Your doctor may also check for tenderness or tightness in the injured area. If the injury is serious or is not healing as expected, your doctor may order an imaging test, such as an ultrasound or MRI. These tests take pictures inside your body.

When your rehab team says you are ready, a few habits may help you run safely. A flat, even surface, such as a track or treadmill, is the safest place to start. Being able to walk 30 minutes with little or no discomfort is a good sign you are ready.

Warming up with 5 to 10 minutes of brisk walking and cooling down with 5 minutes of easy walking helps too. Run at a pace where you can still hold a conversation. If you can't talk, you are pushing too hard.

Your rehab team may make a return-to-running plan for you. The plan should fit your injury, your fitness level, and your goals.

Your plan may include intervals, which are short periods of walking and running that you repeat. It may also include multiple rest days, strength training, and ways to keep track of pain or soreness. And you may do cross-training, such as biking or swimming.

Here is one example of a daily walk-run plan. If your rehab team gives you a different plan, follow theirs. Each session starts with a warm-up and stretches. You do a level once a day and repeat the level for a few days, or until it feels comfortable, before moving to the next. Rest at least 1 day between runs.

• Level 1: Walk 4 minutes, then run 1 minute. Repeat 5 times.
• Level 2: Walk 3 minutes, then run 2 minutes. Repeat 5 times.
• Level 3: Walk 2 minutes, then run 3 minutes. Repeat 5 times.
• Level 4: Walk 1 minute, then run 4 minutes. Repeat 5 times.

If pain is mild and goes away within 24 hours, you may move to the next level.

Mild soreness may be okay for some people. But it should ease up and go away within 24 hours.

If your pain is stronger, lasts longer than 24 hours, or causes you to limp, it may be safer to stay at your current level or go back to an easier one. Contact your doctor if your pain gets worse, swelling does not go down, or you notice any new symptoms.