Wearing properly fitted running shoes is essential for achieving your running goals. The wrong-sized running shoes can cause various injuries and pains, including the typical runner’s knee, IT band syndrome, and shin splints (all extremely irritating). 

Nevertheless, properly fitted running shoes can make you faster, fitter, and stronger; they can prevent injuries regardless of how regularly and far you run. 

Here are seven signs you’re in the wrong size of running shoes:

1. Your feet are getting bruises or “hot spots”

Have you noticed bruised toes or toenails after a run? It’s unpleasant to see, and it’s never a good sign. If you run long-distance races—including half, full, or ultra-marathons—you may witness swelling on your feet; that’s not unusual. However, check your running shoes if your feet are swelling and bruising after ordinary running sessions. 

Wearing poorly fitted shoes will put extra pressure and bruising on your feet, which could impact your overall running performance and cause foot injury. In addition, wrong-sized footwear may cause the dreaded ingrown toenails, leading to swelling, inflamed skin, and infection. If poorly fitted running shoes aren’t generating these issues, it’s likely worn-out shoes, overtraining, or poor technique. 

2. You start noticing blisters

If you notice blisters on your feet, there’s a substantial chance you're wearing the wrong-sized running shoes. Blisters often occur during very long runs (especially marathons). However, that’s not always a cause for concern; your feet simply might not be used to the distance. 

You can significantly reduce nasty blisters by wearing properly-fitted running shoes. Other common causes of blisters include running at a faster pace, inadequate socks, and foot abnormalities like bunions, heel spurs, and hammertoes. However, correctly fitted running shoes can also prevent these problems. 

3. Your running form has changed

A technically sound running technique, including a broad chest, relaxed arms, and soft steps are essential for increased performance and staying injury free. However, poorly fitted running shoes can change your overall running form and cause injuries. 

It can be hard to determine whether your running technique has changed without a running coach. If you start to feel any niggles and pains, it could be a sign of changing running form caused by poorly fitted running shoes. Let an expert watch you run to measure whether your shoes are the foundation of your running woes. 

4. You start getting foot pain (usually on both feet)

There are many reasons your feet may ache during runs, including poor running technique and classic overtraining. However, wearing the wrong-sized running shoes is frequently the cause of foot pain.

The most common pain areas include the heel, the outer foot, the arch, and under the toes. These pains are often caused by plantar fasciitis, Metatarsalgia (pain in the ball of the foot), fat pad syndrome, posterior compartment syndrome, and a stress fracture. You can bypass these foot aches and injuries by wearing well-fitted running shoes. 

5. Your feet feel squashed

You should be able to lift your toes when you wear your running shoes; if not, it’s a sign that your running shoes don’t fit properly. Likewise, your toes shouldn’t rub together inside your shoes because it’s a sign your running shoes are too narrow. 

Remember, all shoes have different shapes and sizes. Always look for and wear shoes that accommodate your natural foot shape. Some people have wider feet, and other people have narrow feet. Either way, an expert can look at your feet and determine the ideal running shoe.

6. You keep getting lower body injuries

… or they never seem to go away. Leg injuries are torture for tens of thousands of runners worldwide. Multiple issues may cause leg injuries, including muscular imbalances, overtraining, poor running technique, and not stretching/massaging your legs before and after running. 

Nevertheless, one of the most prominent causes of leg injuries is wearing the wrong size running shoes because of the added pressure they place on your legs. This can cause shin splints, IT band syndrome, and other common knee problems.

7. You develop tendonitis

Tendons connect your bones and muscles and cause tendonitis when inflaming your tendons. Runners often experience tendonitis in their ankles and feet because their ankle rolls in. However, correctly fitted running shoes can stop your ankles from rolling in and prevent tendonitis. 

It can take 2-3 weeks to recover from tendonitis—a nightmare if you’re training for a race—so stop it by wearing the right size shoe after getting fitted at a run specialty store. 

8. You’ve lost one (or more) toenails 

Losing toenails is NOT part of running. It does, however, mean you’re wearing the wrong size running shoes. 

Your feet can swell up to an entire size in warm weather or during strenuous activity, so buying shoes with at least a two-finger gap between the toes and the tip of the shoe is essential to keep your tootsies from bruising and to keep your toenails intact and alive. 

Runners are not meant to evolve into beings without toenails! 

Improve Your Running Now 

Running shoes are the foundation of every great runner, whereas poorly fitted shoes cause many tiresome running injuries. Wearing well-fitted running shoes is your ticket to better health, fitness, and running times. Most importantly, it’s a golden ticket to staying injury-free.