This article was downloaded by: [University of Massachusetts, Amherst] On: 08 October 2014, At: 13:28 Publisher: Routledge Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK
Journal of Sports Sciences Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/rjsp20
Effects of cold water immersion on lower extremity joint biomechanics during running a
b
Claudiane Arakaki Fukuchi , Emmanuel Souza da Rocha & Darren John Stefanyshyn a
a
Faculty of Kinesiology, University of Calgary, Calgary, Canada
b
Laboratory of Neuromechanics, Federal University of Pampa, Uruguaiana, Brazil Published online: 26 Sep 2014.
To cite this article: Claudiane Arakaki Fukuchi, Emmanuel Souza da Rocha & Darren John Stefanyshyn (2014): Effects of cold water immersion on lower extremity joint biomechanics during running, Journal of Sports Sciences, DOI: 10.1080/02640414.2014.946952 To link to this article: http://dx.doi.org/10.1080/02640414.2014.946952
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions
Journal of Sports Sciences, 2014 http://dx.doi.org/10.1080/02640414.2014.946952
Effects of cold water immersion on lower extremity joint biomechanics during running
CLAUDIANE ARAKAKI FUKUCHI1, EMMANUEL SOUZA DA ROCHA2 & DARREN JOHN STEFANYSHYN1 Faculty of Kinesiology, University of Calgary, Calgary, Canada and 2Laboratory of Neuromechanics, Federal University of Pampa, Uruguaiana, Brazil
Downloaded by [University of Massachusetts, Amherst] at 13:28 08 October 2014
1
(Accepted 17 July 2014)
Abstract The purpose of this study was to identify the influence of cryotherapy on lower extremity running biomechanics. Twenty-six healthy male volunteers were randomised into two intervention groups: cold water (cold water at ~11°C) or tepid water (tepid water at ~26°C). They were required to run at 4.0 ± 0.2 m · s−1 before and after they underwent water immersion for 20 min. Differences between pre- and post-intervention were used to compare the influence of water intervention during running. Peak joint angles, peak joint moments, peak ground reaction forces (GRF) and contact time (CT) were calculated using three-dimensional gait analysis. Independent t-tests were applied with a significant alpha level set at 0.05. Decreased peak propulsive and vertical GRF, decreased plantarflexion moments, increased hip flexion angle and longer CT were observed following cold water immersion. Although cold water immersion (cryotherapy) affected the running movement, none of the alterations have been related to running biomechanical patterns associated with injuries. Therefore, our results indicated that cold water immersion appears safe prior to running activities. Keywords: cryotherapy, biomechanics, running, pre-cooling, injury
Introduction The popularity of cryotherapy has increased among patients and athletes as a form of conservative intervention to aid recovery after soft-tissue trauma by reducing pain, oedema and inflammation, as well as relieving muscle spasm (Knight, 1995). Also, the use of cryotherapy pre-exercise has been adopted by athletes to improve endurance activities (Duffield, Green, Castle, & Maxwell, 2010) by reducing core temperature and delaying the onset of thermally induced fatigue (Wegmann et al., 2012). Although cryotherapy has been proposed to enhance endurance activities (Duffield et al., 2010; Wegmann et al., 2012), it is unknown whether athletes can use it safely prior to engaging in athletic activities. There has been conflicting evidence with studies suggesting either negative (Surenkok, Aytar, Tüzün, & Akman, 2008; Uchio et al., 2003) or no effects (Costello & Donnelly, 2011; LaRiviere & Osternig, 1994; Ozmun, Thieme, Ingersoll, & Knight, 1996) on the ankle and knee joint position sense following the use of cryotherapy.
Additionally, cryotherapy has been negatively related to a reduction of the nerve conduction velocity (Algafly & George, 2007) and muscle-spindle firing rate (Cross, Wilson, & Perrin, 1996), which could alter proprioceptive input and consequently increase the risk of injury. Previous studies have also reported a reduction in strength of the thigh muscles (Howard, Kraemer, Stanley, Armstrong, & Maresh, 1994), peak knee extension torque and power (Dewhurst et al., 2010; Zhou, Carey, Snow, Lawson, & Morrison, 1998), peak plantarflexion torque (Kubo, Kanehisa, & Fukunaga, 2005) as well as alterations in the plantarflexion endurance (Kimura, Thompson, & Gullick, 1997) after cryotherapy. Furthermore, following cold water immersion, performance was also reduced during vertical jumping (Cross et al., 1996; Fisher, Van Lunen, Branch, & Pirone, 2009; Patterson, Udermann, Doberstein, & Reineke, 2008) and running-based agility tests (Evans, Ingersoll, Knight, & Worrell, 1995; Fisher et al., 2009; Patterson et al., 2008). Nevertheless, to date, no studies have investigated the influence of cryotherapy on lower extremity gait
Correspondence: Dr. Darren John Stefanyshyn, Faculty of Kinesiology, University of Calgary, 2500 University Drive NW, Calgary, Alberta, T2N1N4 Canada. E-mail: [email protected] Present address of Claudiane Arakaki Fukuchi is Neuroscience Graduate Program and Biomedical Engineering, Federal University of ABC, São Bernardo do Campo, Brazil. © 2014 Taylor & Francis
Downloaded by [University of Massachusetts, Amherst] at 13:28 08 October 2014
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C. A. Fukuchi et al.
biomechanical patterns, despite the potential impairment in joint proprioception following its use. Cryotherapy could impair an individual’s capacity to respond quickly and efficiently to stimuli, altering running patterns and increasing the risk of injury. A limitation in previous research is the fact that only local effects of cryotherapy have been investigated, for example, by examining the joint position sense as a measure of proprioception. However, despite its increased popularity, the effects of cryotherapy on lower extremity biomechanics during athletic activities such as running remain unknown. In particular, biomechanical parameters that have been associated with musculoskeletal injuries should be examined to ensure it is safe to engage in a physical activity immediately after cryotherapy. Therefore, the purpose of this study was to determine the effects of cryotherapy on lower extremity biomechanics during running in healthy males. In particular, the influence of cryotherapy on joint kinematics, joint kinetics and ground reaction force (GRF) variables was determined. It was hypothesised that participants would demonstrate atypical running biomechanics following cryotherapy.
were recreationally active (engaging in 30 min of moderate physical activity including running or jogging at least 3 days per week). The exclusion criteria involved any circulatory, vestibular or contradiction to cryotherapy including Raynaud’s disease. Prior to the test, each participant signed a consent form approved by the Conjoint Health Research Ethics Board of the University of Calgary. Procedures Prior to the intervention, a neutral standing calibration trial was performed where triads of retro-reflective markers were attached to the right foot (shoe), shank, thigh and pelvis of each participant. Additionally, anatomical markers on the medial and lateral malleoli, medial and lateral epicondyles of the femur and greater trochanter were attached to define the location of the joint centres (Figure 1). The anatomical markers were then removed, and the participants were asked to perform seven valid running trials while they wore standard running shoes (Adizero Mana 5M, adidas International, Herzogenaurach, Germany). Piriyaprasarth and Morris (2007) reported that the average of several trials has been shown to be more reliable than fewer
Methods Participants Twenty-six healthy adult males volunteered to participate in this study and were randomly allocated (n = 13 per group) in either a cold water group (mean age 26.8 years, s = 3.9; height 1.77 m, s = 0.10; mass: 75.6 kg, s = 8.1 and BMI: 24.1 kg · m−2, s = 2.3) or a tepid water group (mean age 22.9 years, s = 3.1; height 1.77 m, s = 0.06; mass 72.1 kg, s = 7.2 and BMI 23.0 kg · m−2, s = 0.2). The sample size was based on previous data from 20 uninjured runners (mean (s) peak knee abduction moment 32.4 (28.27) Nm) that was utilised for the power analysis (Messier et al., 2008). Peak knee abduction moment was chosen for the power analysis, as this variable has been shown to be associated with lower extremity injuries (Fantini Pagani, Potthast, & Brüggemann, 2010). A priori statistical power analysis was conducted to detect the sample size considering an effect size of 1 (α = 0.05 and β = 0.2), as this would conservatively represent a large effect (Cohen, 1992). A minimum of 10 participants per group were required to adequately power this investigation. To account for a potential dropout rate, we chose to recruit 13 participants per group. The randomisation sequence was computer-generated prior to starting the study. The inclusion criteria required that the participants were free of any lower extremity injury in the last 6 months and
Figure 1. Marker set protocol for the pelvis and right lower limb during neutral standing position. Anatomical markers (white) and technical markers (black).
Downloaded by [University of Massachusetts, Amherst] at 13:28 08 October 2014
Effects of cold water immersion on lower extremity trials. A trial was considered valid when the participant landed with their right foot near the middle of the force platform with a running speed of 4.0 ± 0.2 m · s−1, which was monitored using two photocells separated by 1.9 m. The participants were allowed to practice as many trials as necessary in order to familiarise themselves with the procedures before any trial was recorded. Eight motion capture, high-speed cameras (Motion Analysis Corp., Santa Rosa, CA, USA) recorded the three-dimensional (3D) positions of each marker at 240 Hz. Additionally, a force plate (Kistler AG, Winterhur, Switzerland) embedded in the floor collected the GRF data at 2400 Hz. After the baseline data collection, each participant was then randomly assigned to either the cold water group (cold water at ~11°C) or the tepid water group (tepid water at ~26°C). The cold water (Hatzel & Kaminski, 2000; Patterson et al., 2008) and the tepid water (Costello & Donnelly, 2011; Edwards et al., 1972) temperatures were chosen based on the previous literature. They were asked to remain seated in the water tub for 20 min immersed in water up to the umbilical level. Twenty minutes of cryotherapy intervention has been selected based on previous study (Duffield et al., 2010). The water temperature was monitored by using an aquarium thermometer, and the participants were monitored by an independent investigator during the entire immersion period. Participants were allowed to wear dry-fit shorts, and immediately after the intervention, they were required to towel-dry their body and return to the laboratory where the data collection procedures were repeated. Following the cold water intervention, the time frame of assessing the outcome measures was on average 7 min. Data analysis Kinematic and kinetic data throughout the stance phase of running were analysed using Kintrak 7.0 software (Motion Analysis Corp., Santa Rosa, CA, USA). Data were filtered using a fourth-order lowpass Butterworth filter with cut-off frequencies of 8 and 50 Hz for kinematic and kinetic data, respectively (Stackhouse, Davis, & Hamill, 2004). An inverse dynamics approach was used to calculate the internal lower extremity net joint moments during the stance phase of running (Winter, 2009). The initial contact (IC) and peak joint angles and peak joint moments in all three anatomical planes were calculated for the ankle, knee and hip joints. The contact time (CT) (time between IC and takeoff of the stance phase) was also computed. The impact and active peak of the vertical GRF and peak of the braking and propulsive horizontal GRF were defined as the force variables of interested. All
3
joint moments and GRF variables were normalised to body weight (BW), and the time-series curves were time normalised to percent of stance phase (0–100%). The discrete variables were extracted from each of these seven valid trials and averaged across trials to obtain the individual’s average pattern. The differences between pre- and post-intervention (change score) of the calculated variables were then obtained for each participant in both intervention groups and were used for further comparison. Statistical analysis Kolmogorov-Smirnov and Levene’s test were applied to assess normality and homogeneity of the variables, respectively. Independent t-tests were performed to detect differences between the two groups at baseline. Independent t-tests were also carried out to detect the influence of water temperature between-groups employing the differences pre- and post-intervention. Additionally, Cohen’s d effect sizes and 95% confidence intervals were estimated for each variable. A significance level of 0.05 was adopted for all statistical tests that were performed in R software 2.15.1 (R Foundation, Vienna, Austria). Results Detailed results of joint kinematics are presented in Table I. The only statistically significant change score for peak angles was found in the peak hip joint angle (t(24) = 2.62, P = 0.01, d = 1.03), where an increased hip flexion angle was observed after cold water intervention while the control group remained unchanged. During the IC, the change score in hip abduction angle (t(24) = −3.26, P < 0.01, d = 1.28) and hip flexion angle (t (24) = 2.44, P = 0.01, d = 0.96) were significantly greater in the cold water group compared to control, thus indicating that cryotherapy induced less hip abduction and greater hip flexion angles upon landing (Table I). A significantly greater change score was found for peak propulsive horizontal GRF (t(24) = 3.00, P < 0.01, d = 1.18) and peak active vertical GRF (t (24) = 2.22, P = 0.04, d = 0.87) in the cold water immersion group, indicating that cryotherapy induces reduction of both propulsive and vertical active GRF during running. At baseline, the cold water group showed lower braking (P = 0.03) and impact (P = 0.04) forces compared with the tepid group (Table II). The change score for CT was significantly higher in the cold water intervention group (t(24) = −2.25, P = 0.04, d = 0.88), as demonstrated in Table II.
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Table I. Mean (s), within-group mean difference, confidence interval and statistical values of the analysed joint kinematic variables of the right limb for cold and tepid water groups pre- and post-intervention. Pre-intervention
Downloaded by [University of Massachusetts, Amherst] at 13:28 08 October 2014
Variables
Cold
Peak angles (°) Ankle joint Abduction Inversion Plantarflexion Dorsiflexion Knee joint Internal rotation Abduction Flexion Hip joint External rotation Abduction Flexion Initial contact Ankle joint Abduction Inversion Dorsiflexion Knee joint External rotation Abduction Extension Hip joint Internal rotation Abduction Flexion
8.02 11.37 6.82 26.74
(3.29) (2.99) (1.68) (2.19)
Post-intervention
Tepid
8.06 12.99 5.35 24.99
(4.98) (7.87) (3.59) (4.27)
Cold
9.46 11.99 3.84 26.60
(3.14) (4.06) (2.87) (1.89)
Within-group differences
Tepid
8.33 10.95 3.63 24.04
Cold
Tepid
95% CI
(5.15) 1.44 (1.85) 0.27 (1.13) −2.41 (3.53) 0.63 (1.45) −2.04 (6.47) −6.46 (2.73) −2.98 (1.93) −1.73 (3.02) −0.80 (3.27) −0.14 (2.07) −0.95 (3.61) −3.19
−9.60 (4.40) −10.20 (4.74) −9.26 (4.54) −9.42 (3.86) 0.34 (2.19) 3.09 (4.12) 1.42 (3.68) 2.58 (3.44) 1.56 (3.81) −0.51 (1.08) −51.06 (4.90) −47.60 (5.00) −52.79 (3.73) −47.33 (4.77) −1.73 (2.88)
to to to to
Pvalue
0.07 1.13 3.30 1.58
0.06 0.16 0.22 0.49
0.78 (2.07) −1.28 to 2.16 0.15 (0.81) −0.14 to 1.43 0.27 (2.51) −0.18 to 4.19
0.60 0.09 0.07
4.05 (4.14) 6.17 (4.24) 4.84 (4.28) 6.35 (3.74) 0.79 (1.12) 0.18 (1.49) −1.68 to 0.46 −12.15 (3.87) −10.60 (3.22) −12.15 (4.80) −10.64 (3.70) 0.01 (1.77) −0.04 (1.76) −1.46 to 1.38 −36.13 (5.76) −34.15 (5.68) −38.31 (4.43) −34.23 (5.18) −2.18 (2.50) −0.08 (1.45) 0.45 to 3.76
0.25 0.95 0.01*
−0.11 (4.78) −0.35 (1.36) −0.24 (0.70) −0.76 to 0.99 −6.34 (4.91) 0.36 (2.02) −1.10 (6.15) −5.16 to 2.25 11.98 (5.27) −2.31 (2.24) −1.66 (4.87) −2.41 to 3.72
0.79 0.43 0.66
7.11 (5.47) 7.59 (4.92) 8.96 (6.49) 8.05 (5.67) 1.84 (2.99) 0.46 (2.22) −3.52 to 0.75 −1.54 (3.59) −1.60 (3.24) −1.77 (3.53) −1.56 (3.16) −0.24 (0.54) 0.04 (0.73) −0.25 to 0.79 −14.54 (4.17) −11.94 (5.23) −14.96 (3.50) −12.60 (7.11) −0.42 (3.14) −0.66 (2.76) −2.64 to 2.15
0.19 0.29 0.83
1.42 (2.80) −1.78 (3.63) 15.41 (3.20)
0.13 (4.72) −5.24 (8.28) 13.64 (6.72)
1.07 (2.29) −1.42 (4.12) 13.10 (4.04)
−6.33 (5.45) −2.38 (5.04) −5.24 (6.32) −2.67 (5.38) 1.09 (2.32) −0.30 (1.37) −2.92 to 0.16 0.08 −6.51 (3.10) −4.65 (3.85) −4.34 (2.36) −4.89 (3.85) 2.17 (1.90) −0.24 (1.88) −3.94 to −0.88
Journal of Sports Sciences Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/rjsp20
Effects of cold water immersion on lower extremity joint biomechanics during running a
b
Claudiane Arakaki Fukuchi , Emmanuel Souza da Rocha & Darren John Stefanyshyn a
a
Faculty of Kinesiology, University of Calgary, Calgary, Canada
b
Laboratory of Neuromechanics, Federal University of Pampa, Uruguaiana, Brazil Published online: 26 Sep 2014.
To cite this article: Claudiane Arakaki Fukuchi, Emmanuel Souza da Rocha & Darren John Stefanyshyn (2014): Effects of cold water immersion on lower extremity joint biomechanics during running, Journal of Sports Sciences, DOI: 10.1080/02640414.2014.946952 To link to this article: http://dx.doi.org/10.1080/02640414.2014.946952
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions
Journal of Sports Sciences, 2014 http://dx.doi.org/10.1080/02640414.2014.946952
Effects of cold water immersion on lower extremity joint biomechanics during running
CLAUDIANE ARAKAKI FUKUCHI1, EMMANUEL SOUZA DA ROCHA2 & DARREN JOHN STEFANYSHYN1 Faculty of Kinesiology, University of Calgary, Calgary, Canada and 2Laboratory of Neuromechanics, Federal University of Pampa, Uruguaiana, Brazil
Downloaded by [University of Massachusetts, Amherst] at 13:28 08 October 2014
1
(Accepted 17 July 2014)
Abstract The purpose of this study was to identify the influence of cryotherapy on lower extremity running biomechanics. Twenty-six healthy male volunteers were randomised into two intervention groups: cold water (cold water at ~11°C) or tepid water (tepid water at ~26°C). They were required to run at 4.0 ± 0.2 m · s−1 before and after they underwent water immersion for 20 min. Differences between pre- and post-intervention were used to compare the influence of water intervention during running. Peak joint angles, peak joint moments, peak ground reaction forces (GRF) and contact time (CT) were calculated using three-dimensional gait analysis. Independent t-tests were applied with a significant alpha level set at 0.05. Decreased peak propulsive and vertical GRF, decreased plantarflexion moments, increased hip flexion angle and longer CT were observed following cold water immersion. Although cold water immersion (cryotherapy) affected the running movement, none of the alterations have been related to running biomechanical patterns associated with injuries. Therefore, our results indicated that cold water immersion appears safe prior to running activities. Keywords: cryotherapy, biomechanics, running, pre-cooling, injury
Introduction The popularity of cryotherapy has increased among patients and athletes as a form of conservative intervention to aid recovery after soft-tissue trauma by reducing pain, oedema and inflammation, as well as relieving muscle spasm (Knight, 1995). Also, the use of cryotherapy pre-exercise has been adopted by athletes to improve endurance activities (Duffield, Green, Castle, & Maxwell, 2010) by reducing core temperature and delaying the onset of thermally induced fatigue (Wegmann et al., 2012). Although cryotherapy has been proposed to enhance endurance activities (Duffield et al., 2010; Wegmann et al., 2012), it is unknown whether athletes can use it safely prior to engaging in athletic activities. There has been conflicting evidence with studies suggesting either negative (Surenkok, Aytar, Tüzün, & Akman, 2008; Uchio et al., 2003) or no effects (Costello & Donnelly, 2011; LaRiviere & Osternig, 1994; Ozmun, Thieme, Ingersoll, & Knight, 1996) on the ankle and knee joint position sense following the use of cryotherapy.
Additionally, cryotherapy has been negatively related to a reduction of the nerve conduction velocity (Algafly & George, 2007) and muscle-spindle firing rate (Cross, Wilson, & Perrin, 1996), which could alter proprioceptive input and consequently increase the risk of injury. Previous studies have also reported a reduction in strength of the thigh muscles (Howard, Kraemer, Stanley, Armstrong, & Maresh, 1994), peak knee extension torque and power (Dewhurst et al., 2010; Zhou, Carey, Snow, Lawson, & Morrison, 1998), peak plantarflexion torque (Kubo, Kanehisa, & Fukunaga, 2005) as well as alterations in the plantarflexion endurance (Kimura, Thompson, & Gullick, 1997) after cryotherapy. Furthermore, following cold water immersion, performance was also reduced during vertical jumping (Cross et al., 1996; Fisher, Van Lunen, Branch, & Pirone, 2009; Patterson, Udermann, Doberstein, & Reineke, 2008) and running-based agility tests (Evans, Ingersoll, Knight, & Worrell, 1995; Fisher et al., 2009; Patterson et al., 2008). Nevertheless, to date, no studies have investigated the influence of cryotherapy on lower extremity gait
Correspondence: Dr. Darren John Stefanyshyn, Faculty of Kinesiology, University of Calgary, 2500 University Drive NW, Calgary, Alberta, T2N1N4 Canada. E-mail: [email protected] Present address of Claudiane Arakaki Fukuchi is Neuroscience Graduate Program and Biomedical Engineering, Federal University of ABC, São Bernardo do Campo, Brazil. © 2014 Taylor & Francis
Downloaded by [University of Massachusetts, Amherst] at 13:28 08 October 2014
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C. A. Fukuchi et al.
biomechanical patterns, despite the potential impairment in joint proprioception following its use. Cryotherapy could impair an individual’s capacity to respond quickly and efficiently to stimuli, altering running patterns and increasing the risk of injury. A limitation in previous research is the fact that only local effects of cryotherapy have been investigated, for example, by examining the joint position sense as a measure of proprioception. However, despite its increased popularity, the effects of cryotherapy on lower extremity biomechanics during athletic activities such as running remain unknown. In particular, biomechanical parameters that have been associated with musculoskeletal injuries should be examined to ensure it is safe to engage in a physical activity immediately after cryotherapy. Therefore, the purpose of this study was to determine the effects of cryotherapy on lower extremity biomechanics during running in healthy males. In particular, the influence of cryotherapy on joint kinematics, joint kinetics and ground reaction force (GRF) variables was determined. It was hypothesised that participants would demonstrate atypical running biomechanics following cryotherapy.
were recreationally active (engaging in 30 min of moderate physical activity including running or jogging at least 3 days per week). The exclusion criteria involved any circulatory, vestibular or contradiction to cryotherapy including Raynaud’s disease. Prior to the test, each participant signed a consent form approved by the Conjoint Health Research Ethics Board of the University of Calgary. Procedures Prior to the intervention, a neutral standing calibration trial was performed where triads of retro-reflective markers were attached to the right foot (shoe), shank, thigh and pelvis of each participant. Additionally, anatomical markers on the medial and lateral malleoli, medial and lateral epicondyles of the femur and greater trochanter were attached to define the location of the joint centres (Figure 1). The anatomical markers were then removed, and the participants were asked to perform seven valid running trials while they wore standard running shoes (Adizero Mana 5M, adidas International, Herzogenaurach, Germany). Piriyaprasarth and Morris (2007) reported that the average of several trials has been shown to be more reliable than fewer
Methods Participants Twenty-six healthy adult males volunteered to participate in this study and were randomly allocated (n = 13 per group) in either a cold water group (mean age 26.8 years, s = 3.9; height 1.77 m, s = 0.10; mass: 75.6 kg, s = 8.1 and BMI: 24.1 kg · m−2, s = 2.3) or a tepid water group (mean age 22.9 years, s = 3.1; height 1.77 m, s = 0.06; mass 72.1 kg, s = 7.2 and BMI 23.0 kg · m−2, s = 0.2). The sample size was based on previous data from 20 uninjured runners (mean (s) peak knee abduction moment 32.4 (28.27) Nm) that was utilised for the power analysis (Messier et al., 2008). Peak knee abduction moment was chosen for the power analysis, as this variable has been shown to be associated with lower extremity injuries (Fantini Pagani, Potthast, & Brüggemann, 2010). A priori statistical power analysis was conducted to detect the sample size considering an effect size of 1 (α = 0.05 and β = 0.2), as this would conservatively represent a large effect (Cohen, 1992). A minimum of 10 participants per group were required to adequately power this investigation. To account for a potential dropout rate, we chose to recruit 13 participants per group. The randomisation sequence was computer-generated prior to starting the study. The inclusion criteria required that the participants were free of any lower extremity injury in the last 6 months and
Figure 1. Marker set protocol for the pelvis and right lower limb during neutral standing position. Anatomical markers (white) and technical markers (black).
Downloaded by [University of Massachusetts, Amherst] at 13:28 08 October 2014
Effects of cold water immersion on lower extremity trials. A trial was considered valid when the participant landed with their right foot near the middle of the force platform with a running speed of 4.0 ± 0.2 m · s−1, which was monitored using two photocells separated by 1.9 m. The participants were allowed to practice as many trials as necessary in order to familiarise themselves with the procedures before any trial was recorded. Eight motion capture, high-speed cameras (Motion Analysis Corp., Santa Rosa, CA, USA) recorded the three-dimensional (3D) positions of each marker at 240 Hz. Additionally, a force plate (Kistler AG, Winterhur, Switzerland) embedded in the floor collected the GRF data at 2400 Hz. After the baseline data collection, each participant was then randomly assigned to either the cold water group (cold water at ~11°C) or the tepid water group (tepid water at ~26°C). The cold water (Hatzel & Kaminski, 2000; Patterson et al., 2008) and the tepid water (Costello & Donnelly, 2011; Edwards et al., 1972) temperatures were chosen based on the previous literature. They were asked to remain seated in the water tub for 20 min immersed in water up to the umbilical level. Twenty minutes of cryotherapy intervention has been selected based on previous study (Duffield et al., 2010). The water temperature was monitored by using an aquarium thermometer, and the participants were monitored by an independent investigator during the entire immersion period. Participants were allowed to wear dry-fit shorts, and immediately after the intervention, they were required to towel-dry their body and return to the laboratory where the data collection procedures were repeated. Following the cold water intervention, the time frame of assessing the outcome measures was on average 7 min. Data analysis Kinematic and kinetic data throughout the stance phase of running were analysed using Kintrak 7.0 software (Motion Analysis Corp., Santa Rosa, CA, USA). Data were filtered using a fourth-order lowpass Butterworth filter with cut-off frequencies of 8 and 50 Hz for kinematic and kinetic data, respectively (Stackhouse, Davis, & Hamill, 2004). An inverse dynamics approach was used to calculate the internal lower extremity net joint moments during the stance phase of running (Winter, 2009). The initial contact (IC) and peak joint angles and peak joint moments in all three anatomical planes were calculated for the ankle, knee and hip joints. The contact time (CT) (time between IC and takeoff of the stance phase) was also computed. The impact and active peak of the vertical GRF and peak of the braking and propulsive horizontal GRF were defined as the force variables of interested. All
3
joint moments and GRF variables were normalised to body weight (BW), and the time-series curves were time normalised to percent of stance phase (0–100%). The discrete variables were extracted from each of these seven valid trials and averaged across trials to obtain the individual’s average pattern. The differences between pre- and post-intervention (change score) of the calculated variables were then obtained for each participant in both intervention groups and were used for further comparison. Statistical analysis Kolmogorov-Smirnov and Levene’s test were applied to assess normality and homogeneity of the variables, respectively. Independent t-tests were performed to detect differences between the two groups at baseline. Independent t-tests were also carried out to detect the influence of water temperature between-groups employing the differences pre- and post-intervention. Additionally, Cohen’s d effect sizes and 95% confidence intervals were estimated for each variable. A significance level of 0.05 was adopted for all statistical tests that were performed in R software 2.15.1 (R Foundation, Vienna, Austria). Results Detailed results of joint kinematics are presented in Table I. The only statistically significant change score for peak angles was found in the peak hip joint angle (t(24) = 2.62, P = 0.01, d = 1.03), where an increased hip flexion angle was observed after cold water intervention while the control group remained unchanged. During the IC, the change score in hip abduction angle (t(24) = −3.26, P < 0.01, d = 1.28) and hip flexion angle (t (24) = 2.44, P = 0.01, d = 0.96) were significantly greater in the cold water group compared to control, thus indicating that cryotherapy induced less hip abduction and greater hip flexion angles upon landing (Table I). A significantly greater change score was found for peak propulsive horizontal GRF (t(24) = 3.00, P < 0.01, d = 1.18) and peak active vertical GRF (t (24) = 2.22, P = 0.04, d = 0.87) in the cold water immersion group, indicating that cryotherapy induces reduction of both propulsive and vertical active GRF during running. At baseline, the cold water group showed lower braking (P = 0.03) and impact (P = 0.04) forces compared with the tepid group (Table II). The change score for CT was significantly higher in the cold water intervention group (t(24) = −2.25, P = 0.04, d = 0.88), as demonstrated in Table II.
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C. A. Fukuchi et al.
Table I. Mean (s), within-group mean difference, confidence interval and statistical values of the analysed joint kinematic variables of the right limb for cold and tepid water groups pre- and post-intervention. Pre-intervention
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Variables
Cold
Peak angles (°) Ankle joint Abduction Inversion Plantarflexion Dorsiflexion Knee joint Internal rotation Abduction Flexion Hip joint External rotation Abduction Flexion Initial contact Ankle joint Abduction Inversion Dorsiflexion Knee joint External rotation Abduction Extension Hip joint Internal rotation Abduction Flexion
8.02 11.37 6.82 26.74
(3.29) (2.99) (1.68) (2.19)
Post-intervention
Tepid
8.06 12.99 5.35 24.99
(4.98) (7.87) (3.59) (4.27)
Cold
9.46 11.99 3.84 26.60
(3.14) (4.06) (2.87) (1.89)
Within-group differences
Tepid
8.33 10.95 3.63 24.04
Cold
Tepid
95% CI
(5.15) 1.44 (1.85) 0.27 (1.13) −2.41 (3.53) 0.63 (1.45) −2.04 (6.47) −6.46 (2.73) −2.98 (1.93) −1.73 (3.02) −0.80 (3.27) −0.14 (2.07) −0.95 (3.61) −3.19
−9.60 (4.40) −10.20 (4.74) −9.26 (4.54) −9.42 (3.86) 0.34 (2.19) 3.09 (4.12) 1.42 (3.68) 2.58 (3.44) 1.56 (3.81) −0.51 (1.08) −51.06 (4.90) −47.60 (5.00) −52.79 (3.73) −47.33 (4.77) −1.73 (2.88)
to to to to
Pvalue
0.07 1.13 3.30 1.58
0.06 0.16 0.22 0.49
0.78 (2.07) −1.28 to 2.16 0.15 (0.81) −0.14 to 1.43 0.27 (2.51) −0.18 to 4.19
0.60 0.09 0.07
4.05 (4.14) 6.17 (4.24) 4.84 (4.28) 6.35 (3.74) 0.79 (1.12) 0.18 (1.49) −1.68 to 0.46 −12.15 (3.87) −10.60 (3.22) −12.15 (4.80) −10.64 (3.70) 0.01 (1.77) −0.04 (1.76) −1.46 to 1.38 −36.13 (5.76) −34.15 (5.68) −38.31 (4.43) −34.23 (5.18) −2.18 (2.50) −0.08 (1.45) 0.45 to 3.76
0.25 0.95 0.01*
−0.11 (4.78) −0.35 (1.36) −0.24 (0.70) −0.76 to 0.99 −6.34 (4.91) 0.36 (2.02) −1.10 (6.15) −5.16 to 2.25 11.98 (5.27) −2.31 (2.24) −1.66 (4.87) −2.41 to 3.72
0.79 0.43 0.66
7.11 (5.47) 7.59 (4.92) 8.96 (6.49) 8.05 (5.67) 1.84 (2.99) 0.46 (2.22) −3.52 to 0.75 −1.54 (3.59) −1.60 (3.24) −1.77 (3.53) −1.56 (3.16) −0.24 (0.54) 0.04 (0.73) −0.25 to 0.79 −14.54 (4.17) −11.94 (5.23) −14.96 (3.50) −12.60 (7.11) −0.42 (3.14) −0.66 (2.76) −2.64 to 2.15
0.19 0.29 0.83
1.42 (2.80) −1.78 (3.63) 15.41 (3.20)
0.13 (4.72) −5.24 (8.28) 13.64 (6.72)
1.07 (2.29) −1.42 (4.12) 13.10 (4.04)
−6.33 (5.45) −2.38 (5.04) −5.24 (6.32) −2.67 (5.38) 1.09 (2.32) −0.30 (1.37) −2.92 to 0.16 0.08 −6.51 (3.10) −4.65 (3.85) −4.34 (2.36) −4.89 (3.85) 2.17 (1.90) −0.24 (1.88) −3.94 to −0.88
