Isometric exercises do not provide immediate pain relief in Achilles tendinopathy: A quasi-randomized clinical trial

van der Vlist AC, van Veldhoven PLJ, van Oosterom RF, Verhaar JAN, de Vos RJ · Scandinavian Journal of Medicine & Science in Sports

Pain on ten unilateral hops, measured on a 0-100 visual analogue scale before and after, did not fall significantly in any arm: 0.2 (95% CI -11.2 to 11.5) after isometrics in tiptoe position, -1.9 (95% CI -13.6 to 9.7) after isometrics with the ankle dorsiflexed, 1.4 (95% CI -8.3 to 11.1) after isotonic exercise and 7.2 (95% CI -2.4 to 16.7) after rest. No arm separated from another. All four protocols were well tolerated.

Population

Ninety-one patients with clinically diagnosed chronic midportion Achilles tendinopathy

Intervention

One session of isometric calf-muscle exercises, in tiptoe position or with the ankle dorsiflexed

Comparator

Isotonic calf-muscle exercises, or rest

Limitations

Quasi-randomised rather than randomised, and it tests a single session, so it addresses the immediate-analgesia claim and not whether isometrics help over a course of treatment — which the authors say should be studied next. Achilles rather than patellar tendon, and tendon rather than joint. Funded by the Dutch Arthritis Association and the Anna Foundation; the authors declare no conflict of interest.