A runner recently emailed me with a common concern: “Lately my legs feel very heavy and tired during my runs. How can I prevent that?”
I can totally relate — I’ve had plenty of runs when I felt like my legs were made of lead and every step felt like a monumental effort. Like many issues with runners, there’s no one-solution-fits-all for avoiding “heavy legs.” One of the most important steps is to make sure you warm up before your runs with a 5 to 10-minute walk or easy jog. If your legs are feeling tight or tired after your warm-up, do some gentle stretching before getting into the meat of your workout. Make sure you also stretch after your run, when your muscles are warmed-up. Regular stretching will improve your flexibility and the more flexible you are, the better your muscles will absorb the impact of running.
Next, make sure you’re wearing the right shoes. If you have a biomechanical issue, like overpronation (feet rolling in), you may be putting unnecessary stress on certain muscles. Go to a local specialty running store to get a proper shoe fit and make sure you replace your shoes every 300 to 400 miles, since running in worn-out shoes can also make your legs feel tired.
Another possible explanation is overtraining. Make sure you’re not running hard or long two days in a row, and give your body (especially your legs) enough time to rest and recover. Try cutting back on your mileage or your intensity (or both). You can substitute one or two runs each week with cross training activities, such as swimming, rowing, or yoga, which will still build your fitness, while giving your legs a break.
Finally, treat yourself to a deep tissue massage or do some self-massage with a foam roller or other massage tool. That may give you some immediate relief and hopefully prevent future runs with legs of lead.