Lateral ankle sprain is one of the most common sports injuries (Herzog et al., 2019a). Ankle injury rates range from 0.82 to 1.65 injuries per 1,000 exposed athletes, depending on the sport (Lytle et al., 2021). The lateral ankle complex is involved in more than 75% of ankle sprains (Herzog et al., 2019b). Return to play sometimes occurs too soon without respecting athletes' recovery times and full functional recovery (Tassignon et al., 2019), and most of these athletes will have another ankle sprain within the year (Feger et al., 2017; Gribble et al., 2016; McKay et al., 2001; Tassignon et al., 2019). According to various return-to-play models, functional capabilities such as stability should be aspects to consider (Gribble et al., 2016; Smith et al., 2021; THEISEN and DAY, 2019a; THEISEN and DAY, 2019b), because 20% of athletes suffer from chronic ankle instability (Al-Mohrej & Al-Kenani, 2016). The peroneal muscles and surrounding tissues are both active and passive structures in the lateral ankle complex that can be affected by a lateral ankle sprain (Jeon, Lee, Park, & Ha, 2021a, 2021b; THEISEN & DAY, 2019a, THEISEN & DAY, 2019b). The role of the peroneal muscles is to position the ankle in neutral or pronate before the foot touches the ground (Hoch & McKeon, 2014a; Hoch & McKeon, 2014b; Jeon et al., 2021a, 2021b) and so on sprain.
Various studies have observed that after a lateral ankle sprain there is a delay in muscle contraction of the peroneal muscles (Arnold et al., 2009; Hoch and McKeon, 2014a, Hoch and McKeon, 2014b) or even worse reaction forces Ground and modifications of jumping strategies (Jeon et al., 2021a, 2021b). Liu et al. (Liu et al., 2012) observed poorer ground reaction forces in patients after a lateral ankle sprain. These differences include higher peak plantar pressure in the midfoot and lateral forefoot (Nyska et al., 2003), a laterally displaced center of pressure (Ty Hopkins et al., 2012), and higher propulsion and braking forces (Wikstrom & Hass, 2012). ) compared to uninjured participants. Fereydounnia et al. (Fereydounnia et al., 2016) found poorer peroneal muscle reactivity and contraction in patients who sustained ankle sprains in various jumping events. Finally, Caulfield et al. (Caulfield et al., 2004) reported reduced activation of the peroneus longus muscle immediately prior to ground contact during jump landings in these patients. All of these changes can bring the ankle closer to an inversion position and make it more prone to recurrent ankle sprains (de Ridder et al., 2015). Therefore, the correct activation of these muscles seems to be related to the prevention of ankle sprains by reducing the inversion position (Arnold et al., 2009; Hoch and McKeon, 2014a, Hoch and McKeon, 2014b).
Strength and stability training with various tools appears to be effective for lateral ankle sprain rehabilitation (Caldemeyer et al., 2020; Hall et al., 2018; Hung, 2015; Wang, Yu, Kim, & Kan, 2021a, 2021b) . Stability training improves the ability to rapidly position the ankle in a tighter athletic context (Rivera et al., 2017; Schiftan et al., 2015) and a review of the literature shows the effect of instability strength training on stability training, increased ankle muscle strength and stability (Wang et al al., 2021a, 2021b).
These studies have focused on the extent of muscle activity during exercise under conditions where the base of support is unstable, such as Marshall and Murphy, 2006; Wolburg et al., 2016). Typically, unstable loads without surface-induced instability have been induced with chain, tape, or kettlebell weights (Anderson, Gaetz, Holzmann & Twist, 2013a, 2013b). These neuromuscular adaptations during instability training in agonist, antagonist, synergist, and stabilizer muscles can result in increased neural coordination of movements and increased muscle activation (Rutherford & Jones, 1986), resulting in strength gains (Behm et al., 2002) .
A training device currently in vogue for instability training is the water tank. This device is used to create small but rapid disturbances due to inertial changes in the movement of water inside the pipe. During exercise and/or training with this device, the internal redistribution of water within the device creates conditions where the muscle must be activated quickly to keep the water tank stable. The inertial motion caused by the water affects stability and balance, and the amount of water inside the device increases weight and inertial motion (Ditroilo et al., 2018a, 2018b).
Dithroyl et al. (Ditroilo et al., 2018a, 2018b) examined core muscle activity during the water tank squat and observed greater core stabilizing muscle activity during the performance of the squat compared to the traditional barbell. Two years prior to these results, Glass et al. (Glass et al., 2016a, 2016b) examined core muscle activity during the unstable bicep curl using the water tank and found increased steady-state activity in the paraspinal and abdominal muscles. Furthermore, in 2018, the same author found similar results in core activity during overhead squat exercise with the water tank compared to steady state (Glass & Albert, 2018).
To date, the level of activity of the peroneal muscles when performing rehabilitation exercises after ankle sprains with an unstable load such as a water tank is unknown. This data could be important to know if the water tank generates greater activity of this muscle compared to traditional exercises with stable loads.
Therefore, the aim of this study is to evaluate the muscular activity of the peroneus longus muscle during the performance of various resistance and stability exercises with a water tank compared to exercises with a stable load.
The hypothesis of this study is that the exercises performed with a water tank generate greater peroneus longus activity during the performance of various resistance and stability exercises with a stable load.
design and participants
A cross-sectional study was conducted in research laboratory XXXX. The local ethics committee of XXX - CEIm (Comitè d'Ètica d'Investigació amb Medicaments) approved the study protocol (study code: FIS-2022-08). The study procedures were conducted according to the Declaration of Helsinki (World Medical Association, 2013). Informed consent was obtained from all participants.
Surface electromyography based on a similar study by Calatayud was used as the main variable to calculate the sample size.
Figure 2 shows the activation level (RMS) of each exercise.
Repeated measures ANOVA revealed a significant interaction between group and time at RMS (F=51.307, P<0.001, ŋ2=0.70). In the within-group analysis of RMS, we found only statistically significant differences in the stable exercise group between ISLS and RDL (P<0.001, ŋ2=0.05). In the between-group analysis, we found statistically significant differences in RMS ISLS (P<0.001, ŋ2=0.07) (Table 2).
This study aimed to evaluate peroneus longus muscle activity during the execution of ISLS, RDL, LL, and FRFL with unstable load versus stable load.
The results show similarities using the unstable load except in the ISLS exercise and when comparing RDL with stable load to ISLS with stable load.
Training with external components that cause instability requires immediate compensatory adjustments in muscle activity (Anderson et al., 2013a, 2013b; Ditroilo et al., 2018a, 2018b
In conclusion, peroneus longus activity is significantly greater in ISLS exercise with unstable load compared to stable load and peroneus muscle activity in RDL with stable load compared to isometric ISLS with stable load.
This research did not receive specific grants from funding agencies in the public, commercial, or not-for-profit sectors.
The International University of Catalonia – CEIm (Medication Research Ethics Committee) local ethics committee approved the study protocol (study code: FIS-2022-08).
Declaration of Competing Interests
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