Ready for some #fitspo? We're rounding up the best new workouts that'll make you want to hit the gym.

Fitness Trends - Interval Running
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If you've suddenly been inspired to sign up for a marathon (ok, maybe in our case a half-marathon) but are discouraged by the plumb-crazy weather outside. Have heart for there are a bevy of new classes to train those calves and hamstrings into marathon-worthy tone.

Enter the indoor run club.

Ideal for beginners looking to build endurance, starter classes cover a distance of 2 to 3 miles in a 28-minute interval-training session. Once you've built up your stamina, long-distance and marathon-training programs are available. If you're running for more than 30 minutes, wear Vimmia's latest Vimmia X compression leggings to keep your muscles aligned.

Fitness Trends - Interval Running embed
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(Polyester-spandex jacket, Nike, $60; Polyester-elastane sports bra, Under Armour, $30; Mesh sneakers, APL, $140; Nylon-Lycra capris, Vimmia X, $128; Silicone bracelet, flex not included, Tory Burch for Fitbit, $38;

Try It at a Studio

Mile High Run Club in N.Y.C., Shred415 in Chicago, and Tread in Dallas have group classes so engaging that you'll forget you're not hitting the trails outdoors.

Try It at Home

Join Wello (from $49/month) to be paired with a personal coach for one-on-one stamina sessions or small group- training classes through a video chat. Select your ability level and trainer preferences—yep, you can decide whether you want a friendly motivator or a butt- kicking drill sergeant.