Fitness / Running

What’s Causing Heavy Legs on My Runs?

Find out what's making you feel weighed down and how to fix it.

It’s not uncommon for runners to feel a bit slowed down from time to time. Whether it’s the weather, your personal life, or some other cosmic force, sometimes you trudge more than you glide. That lagging feeling typically comes in the form of heavy legs, which basically feels like you accidentally slipped on 50 pound weights instead of your sneakers.

We wish we could promise a running career free of heavy legs, but, sadly we can’t. But here at Aaptiv, we can help you understand what might be causing your pain and what you can do to keep it at bay.

Focus on form

A major potential cause of your heavy legs stems from poor form. Good form is always a key component to running—even when you’re tired, says Aaptiv trainer Jaime McFaden. “When we get tired, we can compromise form, and legs can feel sore or we can even spark injury,” she explains.

To keep proper form, Daniel Giordano, DPT, CSCS Co-Founder of Bespoke Treatments in New York City says to remain light on your feet and keep your feet under your body when striking the ground. Failing to do so can result in overextending, which can throw off your form and potentially cause injury.

And seriously, don’t sacrifice form for pace! Although you might think you’re doing yourself a favor by taking larger strides, you might actually be causing more harm than good. “When you are running at a fast pace, you can also mess up your form easily, so pay attention and stick to a pace that is comfortable for your mind and body before amping it up.”

Think outside the run

It’s not all about what happens on the run. What you do before and after matters, too. You may need to try a few things to help properly warm up before you go out and run, says McFaden. Warm up your joints and muscles with a brisk walk and leg swings.

And don’t forget to stretch (these might help). The post-run stretch is as important as the workout itself, she explains.

“Our bodies were made to work, but we must treat them well by stretching after exercise,” she says. “When you don’t stretch, your muscles will become tight and sore which can lead to muscles feeling so heavy and pained.”

Aaptiv has the perfect stretching classes. Check them out in app today!

Fuel properly

This should come as a no-brainer: you have to fuel your body properly for any workout! “You must have enough nutrients in your body for long runs,” explains McFaden. “If you aren’t hydrated, your body will burn out quick—same goes for nutrition.”

Proper fueling extends beyond race day. Keep it up day in and day out, not just for your audio workouts.  According to Giordano, nutrient deficiency or dehydration can lead to a poor blood supply or fatigue, which can cause serious nerve (neuropathy) or circulation issues. This, of course, leads to heavy legs.

“A lack of iron can mean a lack of hemoglobin [red blood cells], which can lead to a lack of oxygen to your muscles,” he says. “When you’re dehydrated, your blood volume may deplete and lead to fatigue,” he further explains.

Add in strength training

Pair running with strength training to build stronger muscles. This can help support the joints and keep you injury free.

“I always include strengthening exercises to my workout routines,” says McFaden. “Even if you love running, I would advise you to include a few workouts that train the body as a whole.” Consider adding squats, lunges, and burpees to your routine.

Lace up

Your shoes matter. The wrong size, fit, or stability can throw everything off, lead to bad form, and again, may cause injury. “If your trainers are too heavy, your legs can feel heavy,” Giordano says. An uncomfortable shoe problem might also lead to a support problem. “If there is not enough support or cushion, it could lead to excess stress on the joints causing fatigue,” he says.

Thankfully, there are hundreds of different types of shoes on the market. A visit to your running store can have you outfitted for the proper pair. They should conduct a feet test via treadmill to examine your stride, how your feet hit the ground, etc. This will help them match you with the proper shoe for your arches, sole, and how you pronate.

Check your circulation

Circulation might also be to blame. “It’s quite possible that sitting at your desk all day then performing an activity may cause your legs to feel heavy because of circulation,” explains Giordano.

Of course, there are other more serious issues that could be making your legs feel uncomfortable. “Nerve issues, such as peripheral neuropathy can cause a heaviness feeling in the legs,” he explains. And even arthritis can give this effect. Giordano explains that although arthritis affects the joints and causes pain in the joints, the surrounding muscles may overcompensate. If you suspect circulation, nerve, or arthritis issues are the cause of pain, see a doctor to get a proper diagnosis.

For stretching workouts, yoga and more, check out Aaptiv for trainer led classes you’ll love.

Fitness Running


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