Two phrases, used by medical professionals and laypeople alike, are often employed when suggesting that people continue or discontinue pain-provoking activities. These phrases are opposite one another: “If it hurts, don’t do it,” and “No pain, no gain.”

If you ask 100 people which phrase they would use, you would likely get plenty of each response. So, what is the best guideline to follow?

In a way, each can be right at certain times. When they are applicable is 100% dependent on context. Thankfully, we have a way to determine this, which is a simple tool called the traffic light guide.

Like a traffic light, you can have green, yellow, and red lights.

Activities that constitute green lights don’t produce symptoms and, therefore, are safe to perform.

Activities that constitute yellow or red lights require more careful interpretation, as one indicates the activity is safe to perform, and the other indicates the activity should be temporarily avoided. We don’t want to promote unnecessary disability, so differentiating between yellow and red lights is crucial.

In a yellow light activity, any pain produced settles down quickly after stopping. If that is the response, you haven’t damaged tissue or elicited an inflammatory reaction.

A red light activity means that pain remains for a substantial period after stopping. If that is the response, there is a higher likelihood of creating tissue damage and an associated inflammatory response.

Yellow light activities are generally safe to continue, while red light activities should be temporarily avoided or modified until adequate treatment or natural history provides healing.

Range of motion also can be interpreted with the traffic light guide and is a good indicator of whether certain activities are safe.

For example, if you perform an activity and your range of motion isn’t limited after stopping, it would constitute a yellow light. If you perform an activity and your range of motion is worse when you stop, that indicates a red light.

Once you learn how to interpret the traffic light guide, you will become an expert on which activities you can continue and those that should be avoided. Your body will provide the best feedback.

The standard axioms “If it hurts, don’t do it” and “No pain, no gain,” while certainly well-intentioned, don’t provide the best framework for activity in all situations. A better guideline would be “Hurt doesn’t necessarily equal harm,” and the traffic light guide provides valuable, individualized differentiation for each person.

Dr. Jordan Duncan is from Kitsap County and writes a monthly health column for Kitsap News Group. He is the owner of Silverdale Sport & Spine.