Acute Effects of Warming Up on Achilles Tendon Blood Flow and Stiffness

Abstract

Acute effects of warming up on Achilles tendon blood flow and stiffness. J Strength Cond Res 36(10): 2717-2724, 2022-The aim of this study was to investigate the acute effect of frequently used warm-up exercises on the Achilles tendon blood flow and stiffness. In doing so, we want to explore which exercises are suitable to properly prepare the athlete's Achilles tendon in withstanding high amounts of loading during sport activities. This knowledge could help sport physicians and physiotherapists when recommending warm-up exercises that are able to improve sport performance while reducing the injury susceptibility. Achilles tendon blood flow and stiffness measurements of 40 healthy subjects (20 men and 20 women) aged between 18 and 25 years were obtained before and immediately after 4 different warm-up exercises: running, plyometrics, eccentric heel drops, and static stretching. The effect of these warm-up exercises and possible covariates (sex, age, body mass index, rate of perceived exertion, and sports participation) on the Achilles tendon blood flow and stiffness was investigated with linear mixed models. The level of significance was set at a 5 0.05. The results of this study showed a significant increase in Achilles tendon blood flow and stiffness after 10 minutes of running (p , 0.001 and p , 0.001) and plyometrics (p , 0.001 and p 5 0.039). Static stretching and eccentric exercises elicited no significant changes. From these results, it could be suggested that warm-up exercises should be intensive enough to properly prepare the Achilles tendon for subsequent sport activities. When looking at Achilles tendon blood flow and stiffness, we advise the incorporation of highly intensive exercises such as running and plyometrics within warm-up programs.

Myotonometry and extended field-of-view ultrasound imaging allow reliable quantification of patellar tendon stiffness and length at rest and during maximal load, whereas several restrictions exist for the Achilles tendon

“…Our study (Figures 3, 4) and previous studies reported MDCs for PT and AT stiffness and length measurements using the myotonometry method (12,13,15) and the EFOV-US technique (19,20), respectively. With regard to the results of previous studies investigating changes in PT and AT stiffness (31,(48)(49)(50)(51)(52)(53) and length (34, 36-38, 43, 44, 54) in sports and medicine, these changes could be detected outside the measurement error using myotonometry and the EFOV-US technique, which supports the practical applicability of both technologies. For future studies using the EFOV-US technique, and as conducted here, we recommend the usage of a fixable brace to avoid axial shifts of the US probe.…”

Foam rolling and stretching do not provide superior acute flexibility and stiffness improvements compared to any other warm-up intervention: A systematic review with meta-analysis

“…The results of the literature search are illustrated in Fig. 1 , with a total of 38 studies 26 , 27 , 30 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 ( n = 1134 participants, male = 567, female = 415, and 4 studies including 152 participants without information regarding sex; 27 , 39 , 40 , 41 ES: n = 140) meeting the inclusion criteria. Of these, 25 papers compared the effects of stretching to those of alternative activities on ROM; 27 , 39 , 40 , 41 , 42 , 43 , 45 , 46 , 48 , 49 , 51 , 54 , 55 , 57 , 58 , 59 , 60 ,…”

Training habits and lower limb injury prevention in parkour practitioners

“…Although there is no specific parkour-related literature on how to warm-up, a more generic literature can bring some clues. To properly prepare the musculo-skeletal system, and especially lower limb tendons for high plyometric activities, it was shown very recently that warm-up should include sufficient mechanical stress by performing intensive exercise (Pieters et al, 2020), and that stretching or light joint mobility was inefficient or even deleterious. Regarding stretching habits specifically, around 20% of participants reported to stretch before parkour training or during the warm-up.…”

“…Besides inherent physiological factors, the training organization and personal habits also represent an important risk of injury. Especially the presence and importance of warm-up is often reported as an important factor of injury risk particularly in the lower limb (Pieters, Wezenbeek, De Ridder, Witvrouw, & Willems, 2020). Since traceurs must manage important physical constraints, it can also easily be argued that without a proper physical preparation the traceur is exposed to a significantly higher risk of injury.…”