Preventing Plantar Fasciitis in Runners: How Physical Therapy Can Address Strength Asymmetries

Introduction

If you’ve ever trained for a marathon in Denver, you know the toll long miles can take on your body. From sore calves to aching hips, runners constantly navigate the fine line between progress and injury. One of the most common roadblocks? Plantar fasciitis — that stubborn, stabbing heel pain that can derail months of training.

A recent study titled “Interlimb asymmetries of lower limb isometric strength for predicting plantar fasciitis in male amateur marathon runners: a prospective cohort study” shed new light on how hip strength imbalances may predict which runners are at higher risk. This finding is especially relevant for those training on Colorado’s rugged terrain.

So what does this mean for you — and how can Denver Physical Therapy providers use this science to help runners stay healthy and race-ready? Let’s break it down.

Plantar Fasciitis: A Runner’s Nemesis

Plantar fasciitis (PF) is an overuse condition involving irritation of the plantar fascia — the thick band of connective tissue that supports your foot’s arch.

• Symptoms: Sharp heel pain, often worse with first steps in the morning or after long runs.

• Causes: Overtraining, poor footwear, reduced ankle mobility, and muscular imbalances.

• Impact: Accounts for up to 8–10% of all running-related injuries, with marathoners at particularly high risk.

While many runners focus on stretching or icing once pain develops, the real opportunity lies in prevention. That’s where the new study — and modern physical therapy — come in.

What the Study Found

Researchers tested 172 male amateur marathon runners to see if differences in lower-limb strength between the left and right sides (known as interlimb asymmetry) could predict future PF cases. Strength was measured using a force dynamometer across multiple muscle groups.

Key Findings:

• The only significant predictor of plantar fasciitis was hip abduction strength asymmetry (differences in side-to-side glute strength).

• Runners with an asymmetry greater than 32.5% were 3.6 times more likely to develop PF within three months.

• This suggests that even if your calves and hamstrings are strong, an imbalance in hip strength may predispose you to heel pain.

Why Hip Abduction Matters

The gluteus medius and surrounding hip stabilizers play a vital role in controlling pelvic position, knee alignment, and overall gait mechanics. When one side is weaker, it can create compensatory movement patterns that overload the plantar fascia.

Think of it like building a house: if the foundation is uneven, stress cracks appear higher up. For runners, those “cracks” often show up in the heel.

How Denver Physical Therapy Can Help

Here’s where physical therapy makes the leap from research to real-world application. RISE Rehabilitation and Sport Performance is uniquely positioned to assess, correct, and prevent the kinds of asymmetries highlighted in the study.

1. Comprehensive Strength & Movement Screening

A skilled PT doesn’t just treat symptoms — they look for root causes. Using a mix of manual muscle testing, handheld dynamometry, and functional movement analysis, PTs can identify whether you have:

• Side-to-side strength differences (hip abductors, quads, calves).

• Poor movement patterns (knee collapse, pelvic drop, foot pronation).

• Limited mobility in key joints (ankle dorsiflexion, hip extension).

For example, at Rise Rehab and Sport Performance here in Denver, runners often undergo a baseline movement assessment before training cycles. This allows PTs to pick up on small imbalances before they snowball into injury.

2. Addressing Strength Asymmetries

If a PT identifies a hip strength imbalance, the goal is not just to “get stronger,” but to balance strength across both sides.

Evidence-Based Corrective Exercises:

• Side-Lying Hip Abduction: Targets the gluteus medius directly.

• Side Plank Clamshells with Resistance Bands: Reinforces hip stability in a functional range.

• Single-Leg Deadlifts: Builds unilateral hip extension strength.

• Lateral Step-Downs: Incorporates hip control under load, mimicking running demands.

Progressions are carefully prescribed to avoid compensation. For instance, a runner may start with isometric holds, progress to resisted bands, and eventually move into single-leg loaded exercises like Bulgarian split squats or skater lunges.

3. Structured Training Programs

Beyond corrective exercises, PTs design integrated training programs that reduce injury risk while maintaining running performance.

A Structured Program for Runners Might Include:

• Strength Work: 2x/week, focusing on unilateral hip, quad, and calf loading.

• Mobility Drills: Dynamic ankle and hip activations before runs.

• Gait Retraining: Cueing improved cadence, midfoot strike, or pelvic alignment if needed.

• Load Management: Adjusting weekly mileage increases (<10% per week) to prevent overload.

• Recovery Strategies: Soft tissue mobilization, foam rolling, and manual therapy to maintain tissue health.

This structured approach keeps runners on track without sacrificing mileage goals.

4. Bridging Research and Real Life

The study provides a cutoff — 32.5% asymmetry — but in practice, PTs don’t just look at numbers. They integrate findings with your:

• Running volume

• Training surface (think: Denver’s paved paths vs. mountain trails)

• Footwear choices

• Past injury history

For example, a marathoner preparing for the Colfax Marathon may tolerate slight asymmetry if their training is well-balanced, while another with a history of PF may need stricter correction.

Why Denver Runners Should Care

Running in Denver brings unique challenges: higher elevation, more hills, and often, less oxygen to aid recovery. These demands amplify the effects of even small biomechanical imbalances.

That’s why RISE Rehabilitation and Sport Performance supports the running community. By combining local expertise with evidence-backed screening tools, we help ensure runners don’t just finish races — they finish strong and injury-free.

Key Takeaways

• Plantar fasciitis remains one of the most common and frustrating injuries for marathoners.

• New research highlights hip abduction strength asymmetry (>32.5%) as a major risk factor.

• RISE Rehabilitation and Sport Performance can help by:

  • Assessing interlimb asymmetries.

  • Prescribing individualized strength programs.

  • Retraining gait and load patterns.

  • Preventing injury before it starts.

Call to Action

If you’re training for your next marathon, don’t wait until heel pain sidelines you. At RISE Rehabilitation and Sport Performance, we specialize in identifying hidden strength asymmetries, correcting movement patterns, and building programs that keep runners healthy.

Contact us today to schedule a runner’s movement assessment — and let’s make sure plantar fasciitis doesn’t slow you down this season.