The effect of speed on Achilles tendon forces and patellofemoral joint stresses in high‐performing endurance runners

Abstract

Achilles tendinopathy and patellofemoral pain are common running injuries associated with increased Achilles tendon (AT) forces and patellofemoral joint (PFJ) stresses. This study examined AT forces and PFJ stresses at different running speeds in high‐performing endurance runners. Twenty runners ran overground at four running speeds (3.3, 3.9, 4.8, and 5.6 m/s). AT forces and PFJ stresses were estimated from kinematic and kinetic data. Repeated measures ANOVA with partial eta squared effect sizes was conducted to assess differences between running speeds. Increased peak AT forces (19.5%; p < 0.001) and loading rates (57.3%; p < 0.001) from 3.3 m/s to 5.6 m/s were observed. Cumulative AT loading was greater in the faster speeds compared to the slower speeds. Faster running speeds resulted in increased peak plantar flexor moments, increased peak plantar flexion angles, and a more flexed knee and an anterior center of pressure position at touchdown. Peak PFJ stress was lower in the slowest speed (3.3 m/s) compared to the faster running speeds (3.9–5.6 m/s; p = 0.005). PFJ stress loading rate significantly increased (43.6%; p < 0.001). Greater AT loading observed could be associated with strategies such as increased plantar flexor moments and altered lower body position at touchdown which are commonly employed to generate greater ground contact forces. Greater AT and PFJ loading rates were likely due to shorter ground contact times and therefore less time available to reach the peak. Running at faster speeds could increase the risk of developing Achilles tendinopathy and patellofemoral pain or limit recovery from these injuries without sufficient recovery.

The load borne by the Achilles tendon during exercise: A systematic review of normative values

“…With regard to confounders (item 5), some of them such as footwear or level of physical activity were not always taken into consideration. 15,26,27,34,37,39 Moreover, not enough information was given to allow accurate completion of item 12, not all confounders were always defined (item 25), and the power of the study was rarely described (item 27). Details concerning the analysis of each study included in this review are available in Appendix S1.…”

“…The 11 studies included in this review assessed the Achilles tendon load when walking, and/or running, and/or performing strengthening exercises (Table 2). Nine of the eleven studies included a single group of participants, who were required to either (a) perform several activities/exercises, 15,25,27,39 (b) perform the same exercise under different specific conditions, 26,34,35,37 (c) or perform the same exercise but assessed by two different methods. 36 The other two studies compared two groups of participants: male vs female 33 and runners using a rearfoot strike strategy vs those not using this strategy.…”

“…18 The selection of an adequate load for the tendon is thus of utmost importance to induce structural modifications which will improve its resistance and function, thus promoting the healing process. 15,17,19 Over the past 35 years, many studies have attempted to quantify the load borne by the Achilles tendon during various activities, such as cycling, 20,21 walking, 15,[22][23][24][25][26][27] running, 15,22,24,25,[27][28][29][30][31][32][33][34][35][36][37] and strengthening exercises performed with or without additional load. 15,22,25,[38][39][40][41][42][43] To date, no clear progression including all categories of exercises involving the Achilles tendon has been established.…”

Acute Effects of Dermal Suction on Passive Muscle and Joint Stiffness

“…We calculated the 95% confidence interval (CI) for the difference between the mean values. partial η 2 was calculated as the effect size for the main effect and interaction in the two-way ANOVA where 0.01, 0.06, and 0.14 indicated small, medium, and high effects [23]. Additionally, the effect size (r) for the post hoc test was calculated [24].…”

Criteria Identification For Returning To Sport After Achilles Tendon Injury

“…Consequently, we propose a reflection based on the criteria of return to sport validated after the anterior cruciate ligament reconstruction [19,20] or the hamstrings injury [21,22] by adapting them to the operated ATR or not. Analysis of the load applied to the myotendinous junction by the teams of Lai et al, Starbuck et al, as well as Yeh et al [5,23,24] (figure 1), show growth between the upright position, walking, jumping, and running for maximum applied load at the start of the sprint, which correlates with the main injury mechanism of ATR. Therefore, RTS criteria should be based on this progression.…”