Your intuition is pretty reliable when it comes to judging your rate of perceived exertion during exercise. Harness that power for even better workout results

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Turns out, your body may be just as reliable as technology when it comes to measuring excertion in a workout. (Who needs those fancy fitness trackers anyway?) A new study in the Journal of Strength and Conditioning Research finds that self-rated perceived exertion (RPE) (how hard an activity feels to you) is actually an effective tool in helping you judge how hard you're pushing yourself in a workout. (Say What? Your Guide to Exercise Acronyms.)

Though heart rate monitors and other tech can be useful for this too, it's welcome news to us that our own intuition and sense of body awareness is pretty spot on. "We love our gadgets as coaches and athletes, and they are handy for helping you set your pace and giving you immediate feedback," says triathlon coach and exercise physiologist Marni Sumbal, "but I think we shouldn't lose sight of RPE-it's a great tool that never fails (like say, that GPS watch that can't seem to find those darn satellites!)." Plus, using RPE instead of technology helps you to be more in tune with your body during your race or workout, which can help minimize injury risk, amongst other benefits.

For this particular study, researchers tested blood lactate concentration (it rises as you push harder in your workout, so it's a good measure of intensity) while recreational runners ran on a treadmill. The runners were told to rate their perceived exertion on a scale of six (no effort) to 20 (max effort). The numbers may seem a bit odd, but they were chosen because if you multiply them by 10, they should correspond to a heart rate number equivalent to that effort level. (Find out How to Get "in the Zone" for Faster Weight Loss.) But, for the sake of simplicity, Sumbal says you can use a 1 to 10 scale in your own workouts (1 being no effort, 10 being max effort.) The blood test results revealed that the runners were pretty good at estimating their effort level.

If you've never rated your exertion, heed this advice from Sumbal: If you can carry on a conversation, your RPE is low. If you can talk, but not "lead" the conversation (so, you can answer questions in a few words), that's a medium RPE. If you cannot speak at all (and must put all your effort into getting the task at hand done), congrats-you're at a high RPE! In general, know that as you approach the highest intensity you're capable of, your breathing will get heavier, your heart rate will increase, and your muscles may begin to "burn," says Sumbal.

So what's the ideal effort level to aim for? It depends on your goals. "Typically, RPE is associated with how long you can hold a given effort," explains Sumbal. So the higher the RPE, the less time you'd be able to sustain it. For intervals, you'd want to shoot for an eight to nine, an effort level you couldn't sustain for a few minutes-you shouldn't be able to sustain an effort level of nine or ten for longer than one minute. "Most tempo workouts should be around a seven or eight-steady effort, but not easy to communicate, whereas a five to six level of effort allows you to maintain a comfortable conversational pace," says Sumbal. (These 10 Training Songs to Set Your Pace are great for motivation too.)