Postural sway following cryotherapy in healthy adults

The effect of cryotherapy on postural stabilization assessed by standardized horizontal perturbations of a movable platform

BACKGROUND

Cryotherapy is a frequently used therapy in the acute treatment of sports injuries, although it has possible negative effects on dynamic postural stabilization.

RESEARCH QUESTION

What is the effect of cryotherapy on the postural stabilization assessed by imposed platform perturbations?

METHODS

Twenty-four healthy participants (15 male, 9 female) performed 2 test sessions (before and after cryotherapy) consisting of 4 trials each. Each trial included 30 s single leg stance (SLS) on both legs and 4 testing blocks (2 for each leg) of 30 s for the dynamic testing. A single testing block comprised 4 perturbations. After the first session, cryotherapy was applied to the right leg by placing it in ice water at a temperature between 10 °C and 12 ° for 20 min.

OUTCOME MEASURES

We assessed the Center of Pressure speed (CoPs) and the mean force variation for both static and dynamic tests. Additionally, the Time To Stability (TTS) was calculated for the perturbations.

RESULTS

In the static trials there was an interaction between leg and session present for the mean force variation (p = 0.01) with a large η² of 0.24, which shows higher variation of vertical force after application of the cryotherapy on the right leg. During the dynamic trials we found an interaction between leg and session for the TTS suggesting increase of the TTS due to the cryotherapy (p = 0.04), with a large η² of 0.17. No interaction effect was present for the CoPs in the mediolateral and anteroposterior direction (p = 0.62 and p = 0.12, respectively).

SIGNIFICANCE

Cryotherapy applied to the lower extremity results in a worse postural stabilization when assessed by platform perturbations. This might be the result of an altered balance strategy, due to impaired proprioception from the affected body part. More research is needed to examine the duration of this effect.

LEVEL OF EVIDENCE

Level 3, associative study.

Effect of Cryotherapy Temperature on the Extension Performance of Healthy Adults' Legs

Simple Summary

The aim of this study was to investigate the effect of different temperature cryotherapy on leg extension performance. A short period of cold treatment at 0 °C may increase the leg extension ability; however, further lower cold treatment temperatures may cause a decrease in the stretching speed. This may indicate that 0 °C cold therapy for a short period of time is more suitable than −5 °C cold therapy for athletes to recover during the interval within a competition.

Abstract

Cryotherapy as a measurement of sports recovery and treatment has been utilized by more and more athletes and coaches. The aim of this study was to investigate the effect of different temperature cryotherapies on leg extension performance. Thirty-one male participants from a University volunteered to join two different temperature cryotherapies. The peak power and peak force of right leg extension performance of each participant was measured by Keiser, before and after cryotherapy, respectively. The results of this study show that there was a significant difference in peak power (t = −3.203, p value = 0.003) and peak force (t = −4.662, p value = 0) before and after 0 °C cryotherapy. In addition, there was a significant difference in peak force (t = −4.36, p value = 0) before and after −5 °C cryotherapy. Besides, the changing rates of peak power (3.03%) and peak force (11.51%) in the 0 °C group were higher than those of peak power (2.80%), as well as peak force (7.45%), in the −5 °C group. The PF in the 0 °C and −5 °C groups both significantly increased after cryotherapy. Peak power significantly increased after 0 °C cryotherapy, but did not significantly increase after −5 °C cryotherapy. The changing rates of peak power and peak force in the 0 °C group were both higher than the −5 °C group. A short period of cold treatment at 0 °C may increase the leg extension ability. A 0 °C cold therapy for a short period of time is more suitable than a −5 °C one for athletes to recover during the interval within a competition. Athlete and coach could choose an appropriate temperature to help increase performance of physical level and recovery.

The Effect of Cryotherapy Application to the Knee Joint on Dynamic Postural Stability

CONTEXT

Decreased postural balance is a primary risk factor for lower-limb injuries. Cryotherapy is commonly utilized by clinicians to provide local analgesia for minor acute knee joint musculoskeletal injuries during breaks in play or at halftime. Its effect on dynamic postural balance remains unclear.

OBJECTIVE

To investigate the acute effects of a 15-minute knee joint cryotherapy application on dynamic postural balance, as assessed primarily via a clinically oriented outcome measure.

DESIGN

Experimental study.

SETTING

University biomechanics laboratory.

PATIENTS OR PARTICIPANTS

A total of 28 elite-level college male field-sport athletes.

INTERVENTION

Participants were tested on the anterior, posteromedial, and posterolateral reach directions of the Star Excursion Balance Test both before and after a 15-minute knee joint cryotherapy application.

MAIN OUTCOME MEASURE(S)

Normalized reach distances, 3-dimensional knee joint kinematics, sagittal plane hip and ankle joint kinematics, as well as fractal dimension of the center-of-pressure path during the performance of the anterior, posteromedial, and posterolateral reach directions of the Star Excursion Balance Test.

RESULTS

There was a statistically significant decrease in reach distance scores achieved on anterior, posteromedial, and posterolateral directions of the Star Excursion Balance Test from precryotherapy to postcryotherapy (P < .05). None of the decreases in reach distance scores exceeded the reported smallest detectable difference values. No significant differences were observed in hip, knee, or ankle joint kinematics (P > .05). No significant change in fractal dimension was observed for any reach direction following cryotherapy application (P > .05).

CONCLUSIONS

The results of the present study indicate that dynamic postural balance is unlikely to be adversely affected immediately following cryotherapy application to the knee joint.

Effects of plantar hypothermia on quasi-static balance: Two different hypothermic procedures

Inducing hypothermia to examine its effects on balance is performed with various approaches. However, data interpretations of underlying postural mechanisms often do not consider the applied hypothermic protocol. In this context, the effects of diminished plantar mechanoreceptor activity on quasi-static balance performance were investigated, examining the applicability of a continuously cooling thermal platform in comparison with conventional ice pads. Increased instability for the thermal platform compared to cooling with ice pads was hypothesized, since we expected increased temperatures for the ice pad group directly after balance tests. Similar scores on a Visual Analogue Scale (VAS) were predicted regarding subjective pain. Results showed that both cooling procedures successfully induced plantar hypothermia. However, the thermal platform was more effective with respect to reaching and maintaining the desired temperature throughout the trials, especially when comparing temperatures before and after balance tests. Therefore, balance tests indeed demonstrated increased COP parameters exclusively after permanent cooling via the thermal platform as early as after the first 10 min of cooling. Reduced plantar input may result in this postural instability, but without the need of other sensory systems to compensate. The VAS generally demonstrated higher pain scores for the ice pads, rejecting our hypothesis. This is an important finding, since pain is known to influence balance. Therefore, permanent and controllable cooling via the thermal platform should be taken into consideration when conducting related research.

Effects of hypothermically reduced plantar skin inputs on anticipatory and compensatory balance responses

Background

Anticipatory and compensatory balance responses are used by the central nervous system (CNS) to preserve balance, hence they significantly contribute to the understanding of physiological mechanisms of postural control. It is well established that various sensory systems contribute to the regulation of balance. However, it is still unclear which role each individual sensory system (e.g. plantar mechanoreceptors) plays in balance regulation. This becomes also evident in various patient populations, for instance in diabetics with reduced plantar sensitivity. To investigate these sensory mechanisms, approaches like hypothermia to deliberately reduce plantar afferent input have been applied. But there are some limitations regarding hypothermic procedures in previous studies: Not only plantar aspects of the feet might be affected and maintaining the hypothermic effect during data collection. Therefore, the aim of the present study was to induce a permanent and controlled plantar hypothermia and to examine its effects on anticipatory and compensatory balance responses. We hypothesized deteriorations in anticipatory and compensatory balance responses as increased center of pressure excursions (COP) and electromyographic activity (EMG) in response to the hypothermic plantar procedure. 52 healthy and young subjects (23.6 ± 3.0 years) performed balance tests (unexpected perturbations). Subjects’ foot soles were exposed to three temperatures while standing upright: 25, 12 and 0 °C. COP and EMG were analyzed during two intervals of anticipatory and one interval of compensatory balance responses (intervals 0, 1 and 2, respectively).

Results

Similar plantar temperatures confirmed the successful implementation of the thermal platform. No significant COP and EMG differences were found for the anticipatory responses (intervals 0 and 1) under the hyperthermia procedure. Parameters in interval 2 showed generally decreased values in response to cooling.

Conclusion

No changes in anticipatory responses were found possibly due to sensory compensation processes of other intact afferents. Decreased compensatory responses may be interpreted as the additional balance threat, creating a more cautious behavior causing the CNS to generate a kind of over-compensatory behavior. Contrary to the expectations, there were different anticipatory and compensatory responses after reduced plantar inputs, thereby, revealing alterations in the organization of CNS inputs and outputs according to different task difficulties.

A INFLUÊNCIA DA TERMOTERAPIA NO GANHO DE FLEXIBILIDADE DOS MÚSCULOS ISQUIOTIBIAIS

RESUMO Introdução: A flexibilidade muscular é descrita como a capacidade do músculo realizar a extensão de suas fibras, influenciando a mobilidade articular. A diatermia aplicada à musculatura prepara o corpo para atividades físicas, por acelerar o metabolismo das fibras musculares e diminuir a resistência intramuscular, aumentando assim a variedade de movimento e a eficiência mecânica. A crioterapia tem diversas funções fisiológicas quando aplicada ao corpo humano, as quais, em conjunto, propiciam o relaxamento muscular. Objetivo: Avaliar o comportamento da flexibilidade dos músculos isquiotibiais frente à aplicação de alongamento passivo associado a termoterapias quente e fria. Métodos: Este estudo foi composto de 24 voluntários, de ambos os sexos, distribuídos aleatoriamente em três grupos, sendo eles: grupo alongamento passivo (G1), grupo crioterapia precedendo alongamento passivo (G2) e grupo diatermia precedendo alongamento passivo (G3). Os voluntários foram submetidos a avaliações de amplitude de movimento através da goniometria da flexão de quadril com o joelho estendido, sendo uma avaliação inicial realizada antes de iniciar o protocolo e reavaliações ao final de cada uma das quatro semanas de intervenção. Resultados: Verificou-se aumento significativo da flexão de quadril no G2 e G3 com relação ao G1. Não houve diferença estatística entre G2 e G3. Conclusão: O uso da diatermia, assim como da crioterapia, associado ao alongamento passivo é favorável para o ganho de flexibilidade muscular e, consequentemente, de amplitude de movimento em jovens saudáveis.