Getting into the groove of running can be a struggle, especially if you’re just getting started. After all, even long-term runners go through ruts where every mile feels like a suffer-fest.

There are ways, though, to make running feel a little more enjoyable and, well, easier. One way is to use some fun running tests to figure out which parts are more challenging and which come more naturally to you—and tweak your running workouts accordingly.

“Each runner has unique strengths and weaknesses,” Manhattan-based exercise physiologist and certified running coach Ray Peralta, DPT, tells SELF. “Some runners are good with endurance, while others are better at speed sprinting.” Others fall somewhere in the middle.

A lot of this comes down to physiology—or, more specifically, your muscle type. Your muscles are made up of two main types of muscle fibers: slow-twitch and fast-twitch. Slow-twitch fibers are more resistant to fatigue, meaning they can power you for a longer amount of time, but, comparatively speaking, they don’t produce a whole lot of force. Fast-twitch fibers, on the other hand, can produce a lot more force but can’t sustain it for very long. In running, slow-twitch fibers are more suited for long distances, while fast-twitch fibers come in handy for sprinting.

Everyone has both slow-twitch and fast-twitch muscle fibers, but the ratio tends to be different. That means some people may find endurance-based running easier, while others may feel more comfortable with sprints. Your muscle fiber ratio is largely genetic, Peralta says, but how you train can play a small role too.

So how do you know which camp you’re in? Peralta says the only way to scientifically prove what muscle fiber group you fit into is by getting your muscles biopsied. Since nobody wants to get sliced open in the name of recreational running, we asked him to prescribe a few quick running tests to determine which camp we lean toward: speed, speed-endurance, and endurance. That doesn’t mean, however, that your results in these drills should supersede any running goals you may have. For instance, even if your body prefers sprints, you absolutely can run long distances (and learn to love it!) if that’s a goal of yours. That’s why we’ve also provided some tips on how to incorporate different kinds of running into your routine so all aspects of the sport can start to feel a little easier (and more fun!).

How to use these running tests

Do each running drill with at least a two-day rest period in between. Before the test, warm up with a 10-minute walk or jog (or a dynamic warmup), keeping your pace and exertion easy. Afterward, cool down with a five-minute walk or jog. (You can also try this relaxing, yoga-inspired cooldown.)

These tests are best for those who already have an endurance base that allows them to run for at least 10 minutes without stopping. If you’re not quite there yet, you can gradually build up your run endurance with walk-run intervals until you’ve reached that duration without walking. And remember, you can always modify these drill workouts—don’t hesitate to slow down or walk if you need to.