A Female Runner Stretching After A Run On The Sidewalk

A Better Approach for Common Tendon Injuries Might Surprise You

BY Phil White

An increasing body of evidence shows that your clients must consistently load the troublesome tissues once they're out of pain and can perform basic movements to improve their issues.

When one of your athletes starts struggling with a chronic condition like Achilles tendinopathy, runner’s knee or plantar fasciitis, one of three things usually happens. First, they just try to gut it out. Second, you cut back their volume or intensity. Or third, they visit a doctor or PT and are told to rest, ice and stretch the affected area.

The problem with all these approaches is that the first just exacerbates the issue, and the other two are temporary Band-Aids — although mobility should be a part of every athlete’s program and can help treat conditions like runner’s knee. An increasing body of evidence shows that your clients must consistently load the troublesome tissues once they’re out of pain and can perform basic movements to improve their issues. Let’s explore what these studies reveal and how this counterintuitive approach might help clear up your athletes’ chronic injuries for good.

A Better Approach to Achilles Tendinopathy

Achilles tendinopathy is the catch-all term for tendinitis (acute inflammation/soreness) and tendinosis (chronic inflammation and Achilles tendon structure changes). The common perception in the endurance community is that Achilles problems result from too much mileage or intensity.

However, a 2022 study released via Physical Therapy in Sport found that runners with Achilles tendinopathy had several mobility restrictions: less plantar flexion (pointing the toes downward), hip extension and hip abduction. They also had deficits in calf strength and leg curl performance and found it painful to hop. These foot/ankle and hip limitations can be addressed with a few minutes of mobility work each week, while the other issues indicate a potential lack of resistance and plyometric training.[i]

Another group of researchers compared heavy, slow resistance training to eccentric loading (which emphasized muscle lengthening under tension, such as when you slowly lower yourself back down after doing a heel raise).[ii] They concluded that both groups had less pain and swelling and better function after three months and a year.

Other research has found that consistently loading the Achilles tendon causes beneficial mechanical changes that increase its resilience and reduce the risk of injury. So whether your athletes have persistent Achilles issues or want to lower their chances of developing them, performing strength workouts twice or three times a week could help.

Exercises to Solve Plantar Fasciitis

One common treatment method for plantar fasciitis is prescribing shoe inserts, whether these are generic, store-bought insoles or custom orthotics. It’s debatable how beneficial these are, as they do nothing to make the affected tissue more resilient. But if one of your athletes is determined to use an insert, they’d do well to include some strength training in their program.

A study published in the Scandinavian Journal of Medicine & Science in Sports compared the combination of several treatment interventions, with two groups both using shoe inserts while one stretched and the second performed a heel raise strengthening exercise. The researchers concluded that “A simple progressive exercise protocol, performed every second day, resulted in superior self-reported outcome after three months compared with plantar-specific stretching. High-load strength training may aid in a quicker reduction in pain and improvements in function.”[iii]

A literature review on strength training for treating chronic lower limb pain noted that “heavy, slow resistance training (HSRT) and eccentric strengthening interventions having positive outcomes for various lower limb tendinopathies such as plantar heel pain” which can include both plantar fascia and Achilles tendon issues.[iv] But the author was quick to note that such problems often recur because training is not intense or regular enough.

Suggesting, that if your clients do resistance work to try and combat or prevent plantar fasciitis and other chronic lower leg issues, they should do so as part of a continual strength program that includes heavy loading in addition to bodyweight exercises and lower-intensity lifts.

Resistance Training and Runner’s Knee

If someone has been training and competing long enough, they’ve likely experienced occasional soreness and tightness in or around their kneecaps. This is known as runner’s knee, the layperson’s term for patellofemoral pain syndrome.

Your clients might have tried treating this painful condition by taking anti-inflammatories, getting steroid injections, or wearing a knee sleeve or strap. But while these provide temporary relief, they do nothing to change the strength or durability of the muscles, ligaments, and tendons surrounding and intersecting with the knee joint. The same goes for cutting back on training load in believing that overtraining is the issue. In fact, it’s more likely to be under-strengthening.

A study published in the American Journal of Sports Medicine investigated the possible connection between strength training, the long-term relief of runner’s knee, and the functions of the patellar tendon. The authors discovered that not only did strength training reduce pain and improve function, but it also led to significant changes in the density of the tendon.[v] This shows potential for any of your clients who’ve continually struggled with knee pain.

Some of the same researchers conducted another trial that compared cortisone (CORT) injections to eccentric and heavy, slow resistance (HSR) training programs. After three months, everyone noted a decrease in pain and less severe symptoms, but these benefits dropped off for the injection group by the time of a six-month follow-up assessment. They continued for the strength training groups, and those who did the heavy and slow workouts were the most satisfied with their treatment. Lifting weights also increases the production of collagen, which is a building block for connective tissues.

The researchers wrote, “CORT has good short-term but poor long-term clinical effects in patellar tendinopathy. HSR has good short- and long-term clinical effects accompanied by pathology improvement and increased collagen turnover.”[vi] Interestingly, the positive impact of this type of training continued for at least three months after the study stopped, suggesting that it created lasting and beneficial changes. This understanding seems like a good way to sell your clients on the idea of getting in the gym more often.

Strength Exercises for Achilles Tendinopathy, Plantar Fasciitis and Runner’s Knee

Any compound exercise that builds lower body strength and power — such as deadlifts, goblet squats and step-ups — will help increase the durability of your clients’ connective tissues. Box and depth jumps, bounds, hops and other plyometrics will also increase these structures’ elasticity. Isolation exercises focusing on one muscle group or joint are an excellent way to load tissues and increase their tolerance.

I reached out to Dereck Steffe, DPT, from Return to Sport Physio in Evergreen, Colorado, for advice on other movements that can help your athletes overcome chronic conditions like Achilles tendinopathy, runner’s knee, and plantar fasciitis. “The sets and reps of these exercises should be considered ‘as tolerated,'” he said. “Loading the tissue for these injuries is always going to be painful in the first few weeks of rehab. If the pain is getting noticeably worse and doesn’t calm down between sessions, the rep, sets and weight need to be modified.”

Seated Eccentric Heel Raises (for Achilles Tendinopathy)

  • Sit down on a bench, box or chair
  • Place the balls of your feet on a flat object that is 4 to 5 inches tall
  • Raise your heel with all of your weight on the balls of the feet
  • Place and hold a kettlebell or other weight on your knee
  • Slowly lower your heel for a count of five
  • Your heel should finish below the level of your forefoot
  • Remove the weight and raise your heel again
  • Do three sets of 12 reps on each side with a 15-30lb weight every other day for two weeks.
  • A double-leg seated eccentric heel raise is an option if a lower-intensity protocol is needed.
Seated Achilles Exercise

Standing Elevated Heel Raises (for Plantar Fasciitis)

  • Stand on the edge of a step or object that’s 4 to 5 inches tall, balanced on the balls of your feet
  • Raise your heels as high as possible
  • Lift the uninvolved leg so that all of your weight is on the involved one
  • Slowly lower your heel down for a five count, with your heel ending up below the level of the forefoot
  • Return your uninvolved leg to the step and raise your heels back up using BOTH feet
  • Do three sets of 12 reps on each side every other day for two weeks.
  • This is an early rehab exercise, one of the first given by a PT if the athlete can tolerate it. Many people with plantar fasciitis should get comfortable with non-weight-bearing exercises before doing heel raises.
Standing Elevated Heel Raises

Forward Lunges (For Runner’s Knee)

  • Stand with your feet hip-width apart
  • Step forward with one leg, lowering yourself into a lunge position
  • Continue the movement down and forward until your front knee passes your toes and the back knee touches the floor
  • To return to standing, push off with the front heel of the front foot
  • Do two sets of 10-15 reps on each side every other day for two weeks.
  • This exercise is given later in the exercise program when you’d have no pain with walking or sitting. Lunges help transition back to more dynamic activities.
Runners Knee Exercise


[i] Igor Sancho et al., “Recreational Runners with Achilles Tendinopathy Have Clinically Detectable Impairments: A Case-Control Study,” Physical Therapy in Sport, May 2022, available online at https://pubmed.ncbi.nlm.nih.gov/35569332.

[ii] R Beyer et al., “Heavy Slow Resistance Versus Eccentric Training as Treatment for Achilles Tendinopathy: A Randomized Controlled Trial,” American Journal of Sports Medicine, July 2015, available online at https://pubmed.ncbi.nlm.nih.gov/26018970/.

[iii] MS Ratleff et al., “High-Load Strength Training Improves Outcome in Patients with Plantar Fasciitis: A Randomized Controlled Trial with 12-Month Follow-Up,” Scandinavian Journal of Medicine & Science in Sports, June 2015, available online at https://pubmed.ncbi.nlm.nih.gov/25145882.

[iv] Ian Burton, “Autoregulation in Resistance Training for Lower Limb Tendinopathy: A Potential Method for Addressing Individual Factors, Intervention Issues, and Inadequate Outcomes,” Frontiers in Physiology, August 5, 2021, available online at https://www.frontiersin.org/articles/10.3389/fphys.2021.704306/full.

[v] Mads Kongsgaard et al., “Fibril Morphology and Tendon Mechanical Properties in Patellar Tendinopathy: Effects of Heavy Slow Resistance Training,” American Journal of Sports Medicine, February 12, 2010, available online at https://journals.sagepub.com/doi/10.1177/0363546509350915.

[vi] Mads Kongsgaard et al., “Corticosteroid Injections, Eccentric Decline Squat Training and Heavy Slow Resistance Training in Patellar Tendinopathy,” Scandinavian Journal of Medicine & Science in Sports, December 2009, available online at https://pubmed.ncbi.nlm.nih.gov/19793213.

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About Phil White
Phil White is an Emmy-nominated writer and the co-author of The 17 Hour Fast with Dr. Frank Merritt, Waterman 2.0 with Kelly Starrettand Unplugged with Andy Galpin and Brian Mackenzie. Learn more at www.philwhitebooks.com and follow Phil on Instagram @philwhitebooks.

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