Why Does my Heel Hurt So Much During the Power Phase of my Training?
By Jeffrey Rocco M.D. Orthopedic Specialist

Heel pain in athletes is a common problem. Most often heel pain increases during phases of higher intensity and higher volumes of training. There are a number of potential causes of heel pain, but most commonly, the culprit is plantar fascitis. Plantar Fascitis is an inflammation of the plantar fascia. The plantar fascia is a dense, fibrous structure along the sole of the foot, just under the skin. The plantar fascia originates on the bottom of the calcaneus (heel bone) and extends towards the ball of the foot. Symptoms of plantar fascitis can be severe enough to interfere with training and even sometimes simply walking. Inflammation of plantar fascia produces a pain that tends to be at its worst with the first step out of bed in the morning and following high impact activities.

Why do we have a plantar fascia? The plantar fascia mainly acts as a tension band transferring force from the Achilles tendon to the front of the foot. It also helps to maintain the arch of the foot. The plantar fascia facilitates the foot’s ability to function as an efficient lever during gait. The forces transmitted through this lever can be as high as five times body weight. Cadaveric studies have shown that tension in the plantar fascia increases as tension is generated in the Achilles tendon (1,3,4,9). Basically, the forces necessary for forward propulsion must be transmitted through the plantar fascia. As the workload of training increases in volume and intensity, the plantar fascia is at risk for injury.

The plantar fascia, like all connective tissues—including tendons, ligaments and bone, strengthens in response to stress. As one might expect, when those stresses exceed the tissue’s ability to regenerate, injury and pain result. As a general rule, you should probably allow one recovery day between speed and power workouts where intensity meets or exceeds race pace. Recovery does not mean total bedrest. Recovery days are good times to incorporate cross training and work on flexibility and core strength. Very intense workouts probably should be limited to 3 days during the week in the most intense phases of training. The timing of these phases is largely determined by the athlete’s race schedule. Months of lower intensity workouts with perhaps only one speed or power day per week are used to build up gradually to the most intense phases. Scheduling recovery time into your workout plan will strengthen your connective tissues. Neglecting recovery time risks performance-limiting injuries such as plantar fascitis.

What can I do if I have plantar fascitis? Plantar fascitis has been associated with limited ankle dorsiflexion (16) (turning upward of the foot). Most recommendations for non-operative treatment include stretching of the calf muscles and the plantar fascia (7). To this end, night splints have been suggested as treatment for plantar fascitis (2). The night splint is designed to prevent the natural equinus position (downward flexion of the ankle and foot—like a ballerina) that occurs in everyone during sleep.

Modifications to equipment can also help to alleviate plantar fascitis. It is important, as your mileage and intensity increase, to make sure that your running shoes are not worn out. As a rule of thumb, the shock absorption of running shoes decreases dramatically after about 6 months or 500 miles- depending on the size of the runner and the intensity of the efforts. The addition of custom or prefabricated foot orthoses (shoe inserts) has also been used to treat plantar fascitis. However, some recent studies have shown limited benefit to the use of orthotics (12, 14).

More aggressive treatments of plantar fascitis include cortisone injections and extracorporeal shockwave therapy (like that used to break up kidney stones). The results of these treatments have been mixed (10, 13). Traditionally, surgical treatment has focused on heel spur surgery or plantar fascia releases. Authors have reported success with these treatments, but plantar fascia release has been implicated in altered arch mechanics, dorsolateral foot pain, and even continued heel pain (5, 6). For these reasons, I do not personally recommend plantar fascia release to my patients.

Surgical lengthening of the gastrocnemius muscle (superficial layer of the calf muscles) has been found effective at increasing and maintaining ankle dorsiflexion (15). This procedure is performed as an ambulatory procedure through a small incision. The procedure can be performed in about 10 minutes. Following surgery, patients are allowed to weight bear fully in a walking boot. The boot is worn 24/7 during the first 2 weeks, and then during sleep weeks 2-4. Some orthopedic surgeons, including Drs. Manoli, Chilvers, and myself have utilized this procedure to successfully treat recalcitrant plantar fascitis, even in competitive athletes. To document our results, we prospectively evaluated 47 cases of plantar fascitis where non-operative and even previous shockwave and surgical treatment failed to alleviate symptoms. Some of these patients had experienced heel pain for as long as 10 years. There were no complications from surgery, and 93.6% of the patients experienced good or excellent results—relief of pain and return to sports, including running within a few months. (This study was presented at the American Orthopedic Foot and Ankle Surgeons meeting on July 15, 2007, Toronto, Canada. It is currently being reviewed for publication.)

References:
1. Aronow, MS; Diaz-Doran, V; Sullivan, RJ; Adams, DJ: The effect of triceps surae contracture force on plantar foot pressure distribution. Foot Ankle Int. 27: 43-52, 2006.

2. Barry, LD; Barry, AN; Chen, Y: A retrospective study of standing gastrocnemius-soleus stretching versus night splinting in the treatment of plantar fasciitis. J Foot Ankle Surg. 41: 221-227.

3. Carlson, RE; Fleming, LL; Hutton, WC: The biomechanical relationship between the tendoAchilles, plantar fascia and metatarsophalangeal joint dorsiflexion angle. Foot Ankle Int. 21: 18-25, 2000.

4. Cheung, JTK; Zhang, M; An, KN: Effect of Achilles tendon on plantar fascia tension in the standing foot. Clinical Biomech. 21: 194-203.

5. Cheung, JTK; An, KN; Zhang, M: Consequences of partial and total plantar fascia release: a finite element. Foot Ankle Int. 27: 125-132.

6. Crary, JL; Hollis, JM; Manoli, A: The effect of plantar fascia release on strain in the spring and long plantar ligaments. Foot Ankle Int. 24: 245-250.

7. DiGiovanni, BF; Nawoczenski, DA; Lintal, ME; Moore, EA; Murray, JC; Wilding, GE; Baumhauer, JF: Tissue-specific plantar fascia-stretching exercise enhances outcomes in patients with chronic heel pain. J Bone Joint Surg. 85A: 1270-1277, 2003.

8. DiGiovanni, CW; Kuo, R; Tejwani, N; et al: Isolated gastrocnemius tightness. J Bone Joint Surg. 84A: 962-970, 2002.

9. Erdemir, A; Hamel, AJ; Fauth, AR; Piazza, SJ; Sharkey, NA: Dynamic loading of the plantar aponeurosis in walking. J Bone Joint Surg. 86A: 546-552, 2004.

10. Haake, M; Buch, M; Schoellner, C; Goebel, F; Vogel, M; Mueller, I; Hausdorf, J; Zamzow, K; Schade-Brittinger, C; Mueller, HH: Extracorporeal shock wave therapy for plantar fasciitis. BMJ. 327: 75-77.

11. Irving, DB; Cook, JL; Menz, HB: Factors associated with chronic plantar heel pain: a systematic review. J Science Med Sport. 9: 11-22.

12. Landorf, KB; Keenan, AM; Herbert, RD: Effectiveness of foot orthoses to treat plantar fasciitis. Arch Intern Med. 166: 1305-10.

13. Malay, DS; Pressman, MM; Assili, A; Kline, JT; York, S; Buren, B; Heyman, ER; Borowsky, P; LeMay, C: Extracorporeal shockwave therapy versus placebo for the treatment of chronic proximal plantar fasciitis. J Foot Ankle Surg. 45: 196-210.

14. Pfeffer, G; Bacchetti, P; Deland, J; Lewis, A; Anderson, R; Davis, W; Alvarez, R; Brodsky, J; Cooper, P; Frey, C; Herrick, R; Myerson, M; Sammarco, J; Janecki, C; Ross, S; Bowman, M; Smith, R: Comparison of custom and prefabricated orthoses in the initial treatment of proximal plantar fasciitis. Foot Ankle Int. 20: 214-221.

15. Pinney, SJ; Hansen, ST Jr; Sangeorzan, BJ: The effect on ankle dorsiflexion of gastrocnemius recession. Foot Ankle Int. 23: 26-29, 2002.

16. Riddle, DL; Pulisic, M; Pidcoe, P; Johnson, RE: Risk factors for plantar fasciitis: a match case-control study. J Bone Joint Surg. 85A: 872-877, 2003.

17. Wearing, SC; Smeathers, JE; Urry, SR; Hennig, EM; Hills, AP: The pathomechanics of plantar fasciitis. Sports Med. 36: 585-611.