The Effect of Cold Water Immersion on Physiological Indices, Inflammatory and Immune Responses during a Soccer Match / 대한스포츠의학회지

Purpose@#We investigated the effects of cold water immersion (CWI) treatment during half-time break on performance related physiological indices during second half soccer match. @*Methods@#Twenty-two collegiate soccer players participated in the study. Subjects undertook 3 minutes head out seated with whole body immersion at 19 o C to 21 o C. Total four venous blood samples were collected and analyzed for markers of ionic regulations and inflammatory (interleukin [IL]-1b, IL-6, IL-8, IL-10, tumor necrosis factor-α , and vascular endothelial growth factor) and immune functions (immunoglobulin [Ig] G, IgG2, IgG2, IgG3, IgG4, IgA, and IgM). @*Results@#Partial oxygen concentration and %SO 2 level was lowered in CWI. Hemoglobin and hematocrit values were not significantly different between experimental groups. While there was no notable effect was shown in Na ＋ and Ca 2＋ , K ＋ concentration was higher in CWI during second half match. There were no effects in any of inflammatory and/or anti-inflammatory cytokines and Ig. @*Conclusion@#These results suggest that CWI during half time break exert positively affects in buffering capacity and promote oxygen delivery to the actively recruited skeletal muscle, possibly results in improve soccer performance during second half match.

The Changes of Contraction Patterns in Trunk Muscles with Multidirectional Tilting Motion on the Dynamic Posturography / 대한스포츠의학회지

PURPOSE: The aim of this study was to investigate the changes of contraction patterns and the differences of activities in trunk muscles during dynamic balance (multidirectional tilting exercise). METHODS: Eight physically active male subjects participated in the study. Tilting exercises were included by four directions (i.e., forward, backward, left, and right side), and were undertaken at three different tilting degrees (i.e., 10°, 20°, and 30°). They performed two occasions of tilting exercise, separated by 6-week time interval. Surface electromyography system was used for record of any signals produced by muscles which normalized as percentage of maximum voluntary isometric contraction. RESULTS: There were no statistically significant different interactive effects in any of muscles between two factors (time vs. degree). However, we identified significant main effects of degrees (among 10°, 20°, and 30°) in muscle activations during maintaining with forward tilting (left and right longissimus, multifidus), backward tilting (left and right rectus abdominis, external oblique), left side tilting (right rectus abdominis, external oblique, longissimus, multifidus), right side tilting (left rectus abdominis, external oblique, longissimus, multifidus). CONCLUSION: Findings from this study allow the multidirectional tilting exercise to be considered as suitable for ameliorate muscle balance by inducing co-contraction in trunk muscles.

Effect of Forward and Backward Arm Extension Movement of Pilates Exercise Using Cadillac Instrument on Trunk Muscle Activity / 대한스포츠의학회지

PURPOSE: This study analyzed the muscle activity changes induced by motions of reaching forward and chest expansion that were examined from the bilateral muscles with rectus abdominis, external oblique, multifidus, and longissimus thoracic using Pilates cadillac instrument. METHODS: Nine young adult women, who have no musculoskeletal disorder and any of chronic diseases, were participated. Surface electromyography system was used for recording of all signals produced by muscles, and then normalized as percentage of maximum voluntary isometric contraction (%MVIC). The paired t-test and repeated measures of analysis of variance was performed. RESULTS: Reaching-forward motion showed a higher muscle activity from non-dominant external oblique muscle than that of the chest-expansion motion. During both reaching-forward motion and chest-expansion motion, MVIC values collected from dominant side of external oblique muscle were shown a significantly lower than the values obtained from non-dominant side (p < 0.05). Conversely, %MVIC values in external oblique muscle collected from dominant side showed a significantly higher than the values obtained from non-dominant side of the same oblique muscle (p < 0.05). Reaching-forward motion was caused a higher %MVIC on non-dominant external oblique muscle than that of the chest-expansion motion (p < 0.05). Regardless of dominant or non-dominant sides, external oblique muscle was shown the highest activation rate of all the other muscles during reaching forward action, and longissimus thoracic muscle was shown the highest activation rate of all the other muscles during chest expansion action. CONCLUSION: Reaching-forward motion is suitable for activating an external oblique muscle, and chest-expansion motion is an effective enough in activating of longissimus thoracic muscle.

Body Fat Content Does Not Affect Body's Maximal Muscle Strength / 대한스포츠의학회지

We investigated that the relationship between body fat content and maximal muscle strength when skeletal muscle mass was matched. Muscle mass was measured from 140 preliminary selected people, and 30 males were finally selected and divided into one of four experimental groups: low body fat (group 1, ≤11.9%), low-moderate fat (group 2, 12.0%-16.9%), moderate-high fat (group 3, 17.0%-22.9%), high fat (group 4, ≥23.0%). All subjects undertook one repetition maximum (1RM) test of abdominal and back upper body's and lower body's, and bench press, squat, and back strength dynamometer was used. Repeated oneway analysis of variance and Tukey's post-hoc test was adopted to specify mean differences among groups. Statistical significance level was set at α=0.05. 1RM of bench press was not different among groups (p>0.05) even though values from group 2 was marginally higher (15.9%) than group 1 values (p=0.091). 1RM of squat was higher in group 4 compared to group 2 and group 3 (p<0.05), and maximal back muscular strength was higher in group 1 and group 3 than group 2 (p<0.05). However, total 1RM values, sum of 1RM obtained from different exercises, did not reveal any statistical differences. No notable correlation was found between percent body fat (%BF) and maximal muscular strength. Interestingly, negative correlation of muscular strength was observed between %BF and relative (per kilogram) body mass (p<0.001), but not with between %BF and relative skeletal muscle mass. Therefore, it was concluded that maximal muscular strength is influenced not by fat mass but by skeletal muscle mass.

The Effects of Scapular Stabilization Exercise on the Muscular Functions and Pain Release of Shoulder Joints in Youth Baseball Players / 대한스포츠의학회지

We investigated the effect of scapular stabilization exercise on shoulder joints mobilization and pain release in youth baseball players. Total 15 youth baseball players were voluntarily participated, and randomly divided into one of two experimental groups: either stabilization exercise group (EXE, n=7) or control group (NonE, n=8). Stabilization exercises (i.e., punching, scapular retraction, scapular fold, shrug, pull over, seated press, scaption with retraction, body blade, rotator cuff) were administered to EXE (8 weeks, 3 times.wk(-1), 60-100 min.session(-1)). Muscular power using Biodex system 3, full range of motion (ROM) with a goniometer, and the degree of pain with the Visual Analogue Scale was assessed at both baseline and the time point of completion of 8 weeks training program. Twoway ANOVA (group vs. time) was adopted to observe any interactive effects between factors. The statistical significance level was set at alpha=.05. There was an improvement in muscular power at both slow (i.e., 60degrees/sec) and medium (i.e., 180degrees/sec) speed setting in isokinetic instrument during internal and external rotation on dominant shoulder, and internal rotation only (not with external rotation) on non-dominant shoulder. There was no change in ROM in NonE, but total ROM was significantly expanded in EXE, revealing only degree of internal rotation increased. VAS significantly decreased in EXE. In conclusion, scapular stabilization exercise exerted positive effect on muscular power output, full range of motion and pain release on shoulder joint in youth baseball players. This indicates that scapular stabilization exercise possibly exert meaningful effect in injury prevention and sport performance.

The Effect of Visual Information Provision on the Changes of Electromyogram Activity in Trunk and Lower Leg Muscles during Dynamic Balance Control / 대한스포츠의학회지

The purpose of this study was to investigate the changes of electromyogram activity of trunk and lower leg muscles during dynamic balance control in 20 healthy adult subjects when various experimental visual conditions were applied. Surface electromyography system was used for recording of any signals produced by muscles. Muscle activity was recorded from muscles, of which left and right sides of rectus abdominis, external obliques, longissimus thoracis, multifidus, vastus medialis, biceps femoris, gastrocnemius medialis, and tibialis anterior, and then normalized as percentage of maximum voluntary isometric contraction. All data obtained from experiment were analyzed using SPSS ver. 20.0, and two-way analysis of variance were used to determine statistical significance between two factors (3x2 factorial analysis, visual conditions vs. leg conditions). Statistical significance levels were set at alpha=0.05. There were significant different in biceps femoris and external obliques muscle's activities between right and left leg, showing more prominent reduction in left leg when blind vision condition was given. Significantly higher muscle activities were shown in both sides of multifidus (p<0.05), vastus medialis (p<0.001), tibialis anterior (p<0.001) and gastrocnemius medialis (p<0.001) with sighted vision and blanking vision compared to the condition of blind vision. These results confirmed that muscle activity is prominently stimulated by visual information provision, and this implies that visual input may be a major factor for maintaining of the body's balance control.

The Effects of Dietary Interventions on mRNA Expression of Peroxisome Proliferator Activated Receptor Isoforms (PPAR Isoforms)in Rat Skeletal Muscle

We determined the effects of dietary manipulations on messenger RNA of peroxisome proliferators activated receptor isoforms (i.e., PPAR alpha, beta/delta, gamma)in red vastus lateralis muscle of rats. Total 16 male Sprague-Dawley rats were used, and animals were divided into one of two dietary conditions :either chow diet group (CHOW ;n =8 )in which animals were fed with standard rodent chow (61.8% carbohydrate, 15.7% fat, 22.5% protein )or high fat diet group (FAT n =8 ) in which animals were fed 24.3% carbohydrate, 52.8% fat, 22.9% protein. At the end of the 8 weeks of experimental pe-riod, red vastus lateralis muscle was dissected out from all animals, and PPAR alpha, beta/delta, gamma mRNA expression was deter-mined. There was no significant difference in body mass (BM )between CHOW and FAT. As expected, blood glucose and free fatty acid (FFA )concentration was higher in FAT than CHOW (p <0.05 ), and lactate concentration was significan-tly lower in FAT compared to CHOW (p <0.05 ). Insulin concentration tended to higher in FAT than CHOW (67.2 +/- 21.9 vs. 27.0 +/-5.2 pmol/L ), but it did not reach to the statistical significance. Gene expression of PPAR alpha was not signifi-cantly different between CHOW and FAT. It was not also significantly different in PPAR beta/delta. Interestingly, expression of mRNA in PPAR gamma however, was markedly depressed in FAT compared to CHOW (approximately 3 fold higher in CHOW ; p <0.05 ). Results obtained from present study implies that PPAR gamma (as compensatory function of PPAR alpha is expressed ) possibly exerts another major tuning roles in fatty acid transport, utilization, as well as biosynthesis in skeletal muscle cells. The situations and conditions that can be postulated for this implication need to be further examined.

Effects of Dietary Fatty Acid Composition on Pro -and Macro -Glycogen Utilization and Resynthesis in Rat Skeletal Muscle

The purpose of this study was to investigate that the effect of dietary fatty acid composition on pro- and macro-glycogen utilization and resynthesis. The analyses were further extended for different muscle fibers (type I, type II, & type IIb ) as well as tissues (i.e., liver & heart ). Total one hundred sixty Sprague-Dawley rats were used, and rats were randomly allocated into four experimental groups :animals fed standard chow diet (n =40 ), animals fed saturated fatty acid diet (n =40 ), animals fed monounsaturated fatty acid (n =40 ), and animals fed polyunsaturated fatty acid (n =40 ). Animals in each groups were further divided into five subgroups :sacrificed at REST (n =8 ), sacrificed at immediately after 3 hr swim exercise (P-0HR, n =8 ), sacrificed at one hour after 3 hr swim exercise (P-1HR, n =8 ), sacrificed at four hour after 3 hr swim exercise (P-4HR, n =8 ), and sacrificed at twenty-four hour after 3 hr swim exercise (P-24HR, n =8 ). Soleus (type I ), red gastrocnemius (type IIa ), white gastrocnemius (type IIb ), liver, and heart were dissected out at appropriated time point from all animals, and were used for analyses of pro- & macro-glycogen concentrations. After 8 weeks of dietary interventions, there was no significant difference in body mass in any of dietary conditions (p >.05 ). After 3 hr swim exercise, blood lactate level was higher compared to resting conditions in all groups, but it was returned to resting value after 1 hr rest (p .05 ). Regardless of forms of glycogen, the highest level was observed in liver (p <.01 ), and most cases of supercompensation after 3hr exercise observed in this study were occurred in CHOW fed tissues. Except heart muscle, all tissues used in this study showed that pro- and macro-glycogen concentration was significantly decreased after 3 hr exercise. Based on these results, two conclusions were made :first, there is no different level of glycogen content in various tissues regardless of types of fatty acids consumed and second, the highest mobilization rate would be demon-strated from CHOW fed animals compare to animals that consumed any kinds of fatty acid diet if prolonged exercise is applied.