Hyung-pil Jun

Acute effects of whole body vibration on balance in persons with and without chronic ankle instability

ABSTRACT Chronic ankle instability (CAI) is a common condition following ankle injury that is associated with compromised balance. Whole body vibration training (WBVT) programmes are linked with improved balance and function in athletic and non-athletic populations and may improve balance in CAI. Twelve healthy and seven CAI participants completed two randomly assigned interventions. Two Power Plate® platforms were attached back to back using a Theraband®. Participants stood on the active plate and inactive plate for WBVT and sham interventions, respectively. Each intervention included vibration of the active plate. Centre of pressure (COP) and the star excursion balance test (SEBT) were measured before and at 3, 15 and 30 min following the interventions. Significant improvements were found in the anterior direction of the SEBT following both interventions in CAI and varying patterns of improvement were observed for COP measurements in all participants. Therefore, WBVT does not appear to acutely improve balance in CAI.

A Data Set of Human Body Movements for Physical Rehabilitation Exercises

The article presents University of Idaho – Physical Rehabilitation Movement Data (UI-PRMD) — a publically available data set of movements related to common exercises performed by patients in physical rehabilitation programs. For the data collection, 10 healthy subjects performed 10 repetitions of different physical therapy movements, with a Vicon optical tracker and a Microsoft Kinect sensor used for the motion capturing. The data are in a format that includes positions and angles of full-body joints. The objective of the data set is to provide a basis for mathematical modeling of therapy movements, as well as for establishing performance metrics for evaluation of patient consistency in executing the prescribed rehabilitation exercises.

Exercise-induced myokines: a brief review of controversial issues of this decade

ABSTRACT Introduction: Myokines, known to mediate metabolism, inflammation, and other pathophysiological conditions, have been widely investigated, including myokines induced by exercise. However, among published literature, there is substantial inconsistency in the quantification of exercise-induced myokines. Here, we summarized and compared published data regarding the effects of exercise on commonly studied myokines including apelin, Brain-derived neurotrophic factor (BDNF), Interleukin-15 (IL-15), irisin, and Secreted protein acidic and rich in cysteine (SPARC) during the last decade and discussed possible reasons for discrepancy in these reports. Areas covered: A search on PubMed for original articles published in this decade was conducted, focusing on the impacts of exercises on myokines and metabolic and age-related disorders. Beneficial relationship between skeletal muscle plasticity and myokines due to exercise is also discussed. Expert commentary: Based on these analyses, exercise induces the secretion of a number of myokines, which has positive effects on metabolic diseases or age-related muscle atrophy (sarcopenia). However, among published reports, there is wide discrepancy in the quantification of myokines induced by exercise, which could be due to timing of sample collection, pre-analytic sample processing, analytical method, and calculation and other factors. Thus, these factors need to be considered in future studies on exercise induced myokines.

Unilateral Quadriceps Strengthening With Disinhibitory Cryotherapy and Quadriceps Symmetry After Anterior Cruciate Ligament Reconstruction

CONTEXT   The effect of unilateral cryotherapy-facilitated rehabilitation exercise on involved-limb quadriceps function and limb symmetry in individuals with quadriceps dysfunction after anterior cruciate ligament reconstruction (ACLR) remains unclear. OBJECTIVE   To measure the effect of a 2-week unilateral cryotherapy-facilitated quadriceps-strengthening program on knee-extension strength and quadriceps central activation ratio (CAR) in participants with ACLR. DESIGN   Controlled laboratory study. SETTING   Laboratory. PATIENTS OR OTHER PARTICIPANTS   A total of 10 volunteers with unilateral ACLR (1 man, 9 women; age = 21.0 ± 2.8 years, height = 164.6 ± 5.0 cm, mass = 64.0 ± 6.1 kg, body mass index = 23.7 ± 2.7 kg/m2) and 10 healthy volunteers serving as control participants (1 man, 9 women; age = 20.8 ± 2.5 years, height = 169.1 ± 6.2 cm, mass = 61.1 ± 6.4 kg, body mass index = 21.4 ± 2.3 kg/m2) participated. INTERVENTION(S)   Participants with ACLR completed a 2-week unilateral cryotherapy-facilitated quadriceps-strengthening intervention. MAIN OUTCOME MEASURE(S)   Bilateral normalized knee-extension maximal voluntary isometric contraction (MVIC) torque (Nm/kg) and quadriceps CAR (%) were assessed preintervention and postintervention. Limb symmetry index (LSI) was calculated at preintervention and postintervention testing. Preintervention between-groups differences in unilateral quadriceps function and LSI were evaluated using independent-samples t tests. Preintervention-to-postintervention differences in quadriceps function were evaluated using paired-samples t tests. Cohen d effect sizes (95% confidence interval [CI]) were calculated for each comparison. RESULTS   Preintervention between-groups comparisons revealed less knee-extension MVIC torque and quadriceps CAR for the ACLR limb (MVIC: P = .01, Cohen d = -1.31 [95% CI = -2.28, -0.34]; CAR: P = .004, Cohen d = -1.48 [95% CI = -2.47, -0.49]) and uninvolved limb (MVIC: P = .03, Cohen d = -1.05 [95% CI = -1.99, -0.11]; CAR: P = .01, Cohen d = -1.27 [95% CI = -2.23, -0.31]) but not for the LSI (MVIC: P = .46, Cohen d = -0.34 [95% CI = -1.22, 0.54]; CAR: P = .60, Cohen d = 0.24 [95% CI = -0.64, 1.12]). In the ACLR group, participants had improved knee-extension MVIC torque in the involved limb ( P = .04, Cohen d = 0.32 [95% CI = -0.56, 1.20]) and uninvolved limb ( P = .03, Cohen d = 0.29 [95% CI = -0.59, 1.17]); however, the improvement in quadriceps CAR was limited to the involved limb ( P = .02, Cohen d = 1.16 [95% CI = 0.21, 2.11]). We observed no change in the LSI with the intervention for knee-extension MVIC torque ( P = .74, Cohen d = 0.09 [95% CI = -0.79, 0.97]) or quadriceps CAR ( P = .61, Cohen d = 0.26 [95% CI = -0.62, 1.14]). CONCLUSIONS   Two weeks of cryotherapy-facilitated exercise may improve involved-limb quadriceps function while preserving between-limbs symmetry in patients with a history of ACLR.

O25 Immediate effects of ankle taping on joint stiffness and joint angle of the lower extremity during a drop landing

Study Design Control study. Objectives To investigate effects of ankle taping on changes in biomechanics of the lower extremity during drop landing. Background Clinicians often utilise ankle tapings to prevent ankle sprains during practice/competition. Though ankle tapings are regularly employed, the effect of tape application on lower extremity biomechanics is not fully known. Methods and Measures Twenty-eight participants (14 healthy, 14 with chronic ankle instability [CAI]) performed drop landings from a box of 60 cm height (3 before and 3 after traditional ankle taping application). An infrared optical camera system (Vicon Motion Systems Ltd. Oxford, UK) and force-plate (AMTI, Watertown, MA) collected kinematic and kinetic data during drop landing. Stiffness and sagittal angle of the ankle, knee, and hip between initial contact (IC) and maximum knee flexion angle were analysed. Results Sagittal angle of ankle was statistically decreased [Healthy: p<0.05; M±SD: 56.38±55.56(pre), 49.31±5.30(post); CAI: p<0.05; M±SD: 53.12±7.08(pre), 47.68±6.85(post)], while sagittal angles of the knee [Healthy: p>0.05; M±SD: 53.43±8.21(pre), 52.68±7.92(post); CAI: p>0.05; M±SD: 53.26±7.47(pre), 55.16±9.40(post)]and hip [Healthy: p>0.05; M±SD: 30.00±8.62(pre), 30.42±9.16(post); CAI: p>0.05; M±SD: 29.42±6.30(pre), 31.10±7.13(post)] were not significantly changed after taping. Significant decreases in hip stiffness [Healthy: p<0.05; M±SD: 1442.49±413.34(pre), 1113.76±460.90(post); CAI: p<0.05; M±SD: 1313.78±420.54(pre), 1033.33±309.16(post)] and knee stiffness [Healthy: p<0.05; M±SD: 273.09±57.59(pre), 210.02±78.09(post); CAI: p<0.05; M±SD: 244.05±69.85(pre), 201.07±68.74(post)] were found, while ankle stiffness was significantly increased [Healthy: p<0.05; M±SD: 56.38±5.56(pre), 49.31±5.30(post); CAI: p<0.05; M±SD: 53.12±7.08(pre), 46.04±7.97(post)] post-tape application. Conclusions Ankle taping reduces ankle joint angle in a sagittal plane during drop landing and increases ankle stiffness, while also reducing proximal joint stiffness. These findings indicate possible changes in the shock absorption mechanism during landing following ankle tape. Therefore, clinicians may need to consider potential changes in proximal joint movement strategies to attenuate shock during landing following ankle tape application and how this may impact athletic performance or injury risk.

O22 The effects of fibular repositioning taping on joint stiffness and joint angle of the lower extremity during a drop landing

Study Design Control study. Objectives To investigate effects of Fibular Repositioning Taping (FRT) on lower extremity joint stiffness and angle during drop-landing. Background Various taping strategies have been used to prevent ankle sprains. The FRT requires less material and skill than traditional taping. Currently, little is known regarding how FRT effects lower extremity biomechanics. Methods and Measures Twenty-eight participants (14 healthy, 14 with chronic ankle instability [CAI]) performed drop-landings from a 60 cm box; three were performed prior to tape application and three were performed post-FRT. Three-dimensional kinematic and kinetic data were collected using an infrared optical camera system (Vicon Motion Systems Ltd. Oxford, UK) and force-plate (AMTI, Watertown, MA). Joint stiffness and sagittal angle of the ankle, knee, and hip were analysed. Results The hip [Healthy: p<0.05; M±SD: 29.43±11.27(pre), 33.04±12.03(post); CAI: p<0.05; M±SD: 31.45±9.70(pre), 32.29±9.85(post)] and knee [Healthy: p<0.05; M±SD: 53.44±8.09(pre), 55.13±8.36(post); CAI: p<0.05; M±SD: 53.12±8.35(pre), 55.55±9.81(post)] joints demonstrated significant increases in sagittal angle after FRT. A significant decrease in joint angle was found at the ankle [Healthy: p<0.05; M±SD: 56.10±3.71(pre), 54.09±4.31(post); CAI: p<0.05; M±SD: 52.80±6.04(pre), 49.86±10.08(post)]. A significant decrease in hip [Healthy: p<0.05; M±SD: 1549.16±517.53(pre), 1272.48±646.73(post); CAI: p<0.05; M±SD: 1300.42±595.55(pre), 1158.27±550.58(post)] and knee [Healthy: p<0.05; M±SD: 270.12±54.07(pre), 239.13±64.70(post); CAI: p<0.05; M±SD: 241.58±93.48(pre), 214.63±101.00(post)] joint stiffness was found post-FRT application, while no difference was found at the ankle [Healthy: p>0.05; M±SD: 57.29±17.04(pre), 59.37±18.30(post); CAI: p>0.05; M±SD: 69.15±17.63(pre), 77.24±35.05(post)]. Conclusion FRT application decreased joint angle at the ankle without altering ankle joint stiffness. In contrast, decreased joint stiffness and increased joint angle was found at the hip and knee following FRT. Thus, participants utilise an altered shock absorption mechanism during drop-landings following FRT. When compared to previous research, the joint kinematics and stiffness of the lower extremity appear to be different following FRT versus traditional ankle taping.

ANKLE BIOMECHANICS AND JUMP PERFORMANCE IN HEALTHY AND CHRONIC ANKLE INSTABILITY INDIVIDUALS DURING LANDING: A TRIPLE BLIND RANDOMIZED CLINICAL TRIAL OF ANKLE TAPING EFFICACY

Background Clinicians regularly utilize ankle taping procedures to prevent ankle sprains during practice/competition. Though many different ankle taping applications are employed, the effect of these on biomechanics and performance is unknown. Objective To investigate changes in ankle biomechanics during landing and jump performance with ankle taping. Design Triple-blind randomized. Setting University laboratory. Participants Twenty-eight participants (14 healthy, 14 with chronic ankle instability [CAI]). Interventions Each participant was assigned to a randomized order of three taping applications (1: Traditional Taping [TT], 2: Mulligan Concept Taping [MT], and 3: Kinesiology Taping [KT]) and performed maximum vertical jump and running-stop jump-landings (3 before and 3 after) each ankle taping application. An eight infrared optical cameras system (Vicon Motion Systems Ltd. Oxford, UK) and force plate (AMTI, Watertown, MA) were used to collect all kinematics and kinetics data during running-stop jump-landing. Main Outcome Measurements Maximum height of vertical jump and excursion of dorsiflexion (DF) and inversion (IV) of the ankle between 100 ms before and after initial contact (IC). Results A statistically significant difference for the main effects of tape application [F(2,26)=0.06, p=0.94, M±SD: 0.82±12.55(TT), 1.29±8.64 (MT), 0.42±10.31 (MT); F(2,26)=0.58, p=0.46, M±SD: 0.58±1.38(TT), 0.67±0.65(MT), 0.48±0.97(MT)] and interactions [F(2,26)=0.89, p=0.51; F(2,26)=0.46, p=0.41] on changes of DF and IV were not found regardless of tape application. For MVJ, a statistically significant change across tape application was not found [F(2,26)=0.65, p=0.49]; however, a statistically significant interaction on MVJ was found in the CAI group with KT application[F(2,26)=3.50, p=0.04, M±SD: 0.30±0.69 [Healthy]; −0.36±0.88 [CAI]). Conclusions The use of tape did not have any significant impact on ankle biomechanics during landing. Using KT produced a significant change in MVJ in participants with CAI, but the improvement is unlikely to be clinically meaningful. The use of these taping methods to improve ankle biomechanics or improve jump performance in healthy athletes, or those with CAI, is questionable.

THE EFFECT OF ANKLE TAPING ON SHOCK ABSORPTION CHARACTERISTICS OF LOWER EXTREMITY

Background Ankle taping has been widely used to prevent recurrent ankle sprain during dynamic tasks. However, it may alter joint stiffness result in an adverse effect on a shock absorption to the entire lower extremity kinetic chain during landing due to a restricted ankle joint. Objective To investigate changes in lower extremity biomechanics with and without taping during drop landing (DL). Design Case control study. Setting Laboratory. Patients (or Participants) A total of active 53 male college students with no history of lower extremity surgery or injury were participated. Interventions Each participant performed eight drop landings (four before and four after ankle taping). Eight infrared-optical cameras system (Vicon Motion Systems Ltd. Oxford, UK) and force-plates (Bertec Corporation. Columbus, OH) were used to collect all kinematics and kinetics during DL. Main Outcome Measurements Sagittal plane joint kinematics and kinetics were extracted between initial contact and maximum knee flexion angle. Cohens D effect size (d) and 95% confidence interval (CI) were calculated to analyze size of difference. Results Sagittal plane total excursion of the ankle was statistically decreased (d=1.01, CI:0.61∼1.42) but knee and hip were not changed after taping. Joint stiffness showed no significant changes at the ankle (d=−0.25, CI:−0.63∼0.13), knee (d=−0.11, CI:−0.49∼0.27), and hip (d=−0.12, 95% CI:−0.51∼0.26) after taping There were significant decrease in both eccentric work (d=−0.78, 95% CI:−1.18∼-0.39) and contribution to total work (d=0.58, CI:0.19∼0.97) at ankle while no changes observed in the knee and the hip. Conclusions Even though ankle taping reduces ankle joint total excursion during DL and may impact on ankle stiffness, it does not alter proximal joint kinematics and stiffness. Reduced both eccentric work and%work at the ankle joint indicates possible changes in shock absorption mechanism during landing. Therefore, the clinicians may consider the importance of proximal joint movement strategy to attenuate shock during landing.