TY - JOUR A1 - Mühlbauer, Thomas A1 - Pabst, Jan A1 - Granacher, Urs A1 - Buesch, Dirk T1 - Validity of the jump-and-reach test in subelite adolescent handball players JF - Journal of strength and conditioning research : the research journal of the NSCA KW - Vertec device KW - Optojump system KW - vertical jump height KW - field test KW - athlete testing KW - region/point elastic gym floor Y1 - 2017 U6 - https://doi.org/10.1519/JSC.0000000000001607 SN - 1064-8011 SN - 1533-4287 VL - 31 SP - 1282 EP - 1289 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Helm, Norman A1 - Prieske, Olaf A1 - Mühlbauer, Thomas A1 - Krüger, Tom A1 - Chaabene, Helmi A1 - Granacher, Urs T1 - Validation of a new judo-specific ergometer system in male elite and sub-elite athletes JF - Journal of sports science & medicine N2 - Our experimental approach included two studies to determine discriminative validity and test-retest reliability (study 1) as well as ecological validity (study 2) of a judo ergometer system while performing judo-specific movements. Sixteen elite (age: 23 +/- 3 years) and 11 sub-elite (age: 16 +/- 1 years) athletes participated in study 1 and 14 male sub-elite judo athletes participated in study 2. Discriminative validity and test-retest reliability of sport-specific parameters (mechanical work, maximal force) were assessed during pulling movements with and without tsukuri (kuzushi). Ecological validity of muscle activity was determined by performing pulling movements using the ergometer without tsukuri and during the same movements against an opponent. In both conditions, electromyographic activity of trunk (e.g., m. erector spinae) and upper limb muscles (e.g., m. biceps brachii) were assessed separately for the lifting and pulling arm. Elite athletes showed mostly better mechanical work, maximal force, and power (0.12 <= d <= 1.80) compared with sub-elite athletes. The receiver operating characteristic analysis revealed acceptable validity of the JERGo(C) system to discriminate athletes of different performance levels predominantly during kuzushi without tsukuri (area under the curve = 0.27-0.90). Moreover, small-to-medium discriminative validity was found to detect meaningful performance changes for mechanical work and maximal force. The JERGo(C) system showed small-to-high relative (ICC = 0.37-0.92) and absolute reliability (SEM = 10.8-18.8%). Finally, our analyses revealed acceptable correlations (r = 0.41-0.88) between muscle activity during kuzushi performed with the JERGo(C) system compared with a judo opponent. Our findings indicate that the JERGo(C) system is a valid and reliable test instrument for the assessment and training of judo-specific pulling kinetics particularly during kuzushi movement without tsukuri. KW - Judo-specific pulling movement KW - work KW - force KW - muscle activity KW - reliability Y1 - 2018 SN - 1303-2968 VL - 17 IS - 3 SP - 465 EP - 474 PB - Department of Sports Medicine, Medical Faculty of Uludag University CY - Bursa ER - TY - JOUR A1 - Granacher, Urs A1 - Prieske, Olaf A1 - Majewski, M. A1 - Büsch, Dirk A1 - Mühlbauer, Thomas T1 - The Role of Instability with Plyometric Training in Sub-elite Adolescent Soccer Players JF - International journal of sports medicine N2 - The purpose of this study was to investigate the effects of plyometric training on stable (SPT) vs. highly unstable surfaces (IPT) on athletic performance in adolescent soccer players. 24 male sub-elite soccer players (age: 15 +/- 1 years) were assigned to 2 groups performing plyometric training for 8 weeks (2 sessions/week, 90min each). The SPT group conducted plyometrics on stable and the IPT group on unstable surfaces. Tests included jump performance (countermovement jump [CMJ] height, drop jump [DJ] height, DJ performance index), sprint time, agility and balance. Statistical analysis revealed significant main effects of time for CMJ height (p<0.01, f=1.44), DJ height (p<0.01, f=0.62), DJ performance index (p<0.05, f=0.60), 0-10-m sprint time (p<0.05, f=0.58), agility (p<0.01, f=1.15) and balance (p<0.05, 0.46f1.36). Additionally, a Training groupxTime interaction was found for CMJ height (p<0.01, f=0.66) in favor of the SPT group. Following 8 weeks of training, similar improvements in speed, agility and balance were observed in the IPT and SPT groups. However, the performance of IPT appears to be less effective for increasing CMJ height compared to SPT. It is thus recommended that coaches use SPT if the goal is to improve jump performance. KW - strength KW - jump KW - speed KW - agility KW - balance Y1 - 2015 U6 - https://doi.org/10.1055/s-0034-1395519 SN - 0172-4622 SN - 1439-3964 VL - 36 IS - 5 SP - 386 EP - 394 PB - Thieme CY - Stuttgart ER - TY - JOUR A1 - Prieske, Olaf A1 - Mühlbauer, Thomas A1 - Krüger, Tom A1 - Kibele, A. A1 - Behm, David G. A1 - Granacher, Urs T1 - Sex-Specific effects of surface instability on drop jump and landing biomechanics JF - International journal of sports medicine N2 - This study investigated sex-specific effects of surface instability on kinetics and lower extremity kinematics during drop jumping and landing. Ground reaction forces as well as knee valgus and flexion angles were tested in 14 males (age: 23 +/- 2 years) and 14 females (age: 24 +/- 3 years) when jumping and landing on stable and unstable surfaces. Jump height was found to be significantly lower (9 %, p < 0.001) when drop jumps were performed on unstable vs. stable surface. Significantly higher peak ground reaction forces were observed when jumping was performed on unstable vs. stable surfaces (5 %, p = 0.022). Regarding frontal plane kinematics during jumping and landing, knee valgus angles were higher on unstable compared to stable surfaces (1932 %, p < 0.05). Additionally, at the onset of ground contact during landings, females showed higher knee valgus angles than males (222 %, p = 0.027). Sagittal plane kinematics indicated significantly smaller knee flexion angles (6-35 %, p < 0.05) when jumping and landing on unstable vs. stable surfaces. During drop jumps and landings, women showed smaller knee flexion angles at ground contact compared to men (27-33 %, p < 0.05). These findings imply that knee motion strategies were modified by surface instability and sex during drop jumps and landings. KW - stretch-shortening cycle KW - ground reaction force KW - knee joint angle KW - injury risk Y1 - 2015 U6 - https://doi.org/10.1055/s-0034-1384549 SN - 0172-4622 SN - 1439-3964 VL - 36 IS - 1 SP - 75 EP - 81 PB - Thieme CY - Stuttgart ER - TY - JOUR A1 - Mühlbauer, Thomas A1 - Gollhofer, Albert A1 - Granacher, Urs T1 - Sex-related effects in strength training during adolescence a pilot study JF - Perceptual & motor skills N2 - The objective was to investigate the effects of high-velocity strength training on isometric strength of the leg extensors and jump height in female and male adolescents. Twenty-eight students (13 boys, 15 girls) ages 16 to 17 years participated in this study and were assigned to either a strength training group or a control group. Strength training was conducted over 8 weeks (2 times per week). Pre- and post-training tests included the measurements of maximal isometric force and rate of force development of the leg extensors as well as countermovement jump height. Both girls (effect size = 1.37) and boys (effect size = 0.61) showed significant improvements in jump height. However, significant increases in maximal isometric force (effect size = 1.85) and rate of force development (effect size = 2.23) were found only in girls. In female and male adolescents, high-velocity strength training is an effective training regimen that produced improvements in countermovement jump height in both sexes but higher gains in maximal isometric force and rate of force development in girls. Y1 - 2012 U6 - https://doi.org/10.2466/06.10.30.PMS.115.6.953-968 SN - 0031-5125 VL - 115 IS - 3 SP - 953 EP - 968 PB - Sage Publ. CY - Missoula ER - TY - JOUR A1 - Prieske, Olaf A1 - Mühlbauer, Thomas A1 - Krüger, Tom A1 - Kibele, Armin A1 - Behm, David G. A1 - Granacher, Urs T1 - Role of the trunk during drop jumps on stable and unstable surfaces JF - European journal of applied physiology N2 - The present study investigated associations between trunk muscle strength, jump performance, and lower limb kinematics during drop jumps on stable and unstable surfaces. Next to this behavioral approach, correlations were also computed on a neuromuscular level between trunk and leg muscle activity during the same test conditions. Twenty-nine healthy and physically active subjects (age 23 +/- A 3 years) were enrolled in this study. Peak isokinetic torque (PIT) of the trunk flexors and extensors was assessed separately on an isokinetic device. In addition, tests included drop jumps (DJ) on a force plate under stable and unstable (i.e., balance pad on top of the force plate) surfaces. Lower limb kinematics as well as electromyographic activity of selected trunk and leg muscles were analyzed. Significant positive but small correlations (0.50 a parts per thousand currency sign r a parts per thousand currency sign 0.66, p < 0.05) were detected between trunk extensor PIT and athletic performance measures (i.e., DJ height, DJ performance index), irrespective of surface condition. Further, significant negative but small correlation coefficients were examined between trunk extensor PIT and knee valgus motion under stable and unstable surface conditions (-0.48 a parts per thousand currency sign r a parts per thousand currency sign -0.45, p < 0.05). In addition, significant positive but small correlations (0.45 a parts per thousand currency sign r a parts per thousand currency sign 0.68, p < 0.05) were found between trunk and leg muscle activity, irrespective of surface condition. Behavioral and neuromuscular data from this study indicate that, irrespective of the surface condition (i.e., jumping on stable or unstable ground), the trunk plays a minor role for leg muscle performance/activity during DJ. This implies only limited effects of trunk muscle strengthening on jump performance in the stretch-shortening cycle. KW - Core stability KW - Jump height KW - Knee valgus motion KW - Ground reaction force KW - Stretch-shortening cycle KW - Electromyography Y1 - 2015 U6 - https://doi.org/10.1007/s00421-014-3004-9 SN - 1439-6319 SN - 1439-6327 VL - 115 IS - 1 SP - 139 EP - 146 PB - Springer CY - New York ER - TY - JOUR A1 - Granacher, Urs A1 - Lacroix, Andre A1 - Roettger, Katrin A1 - Gollhofer, Albert A1 - Mühlbauer, Thomas T1 - Relationships between trunk muscle strength, spinal mobility, and balance performance in older adults JF - Journal of aging and physical activity N2 - This study investigated associations between variables of trunk muscle strength (TMS), spinal mobility, and balance in seniors. Thirty-four seniors (sex: 18 female, 16 male; age: 70 +/- 4 years; activity level: 13 +/- 7 hr/week) were tested for maximal isometric strength (MIS) of the trunk extensors, flexors, lateral flexors, rotators, spinal mobility, and steady-state, reactive, and proactive balance. Significant correlations were detected between all measures of TMS and static steady-state balance (r = .43.57, p < .05). Significant correlations were observed between specific measures of TMS and dynamic steady-state balance (r = .42.55, p < .05). No significant correlations were found between all variables of TMS and reactive/proactive balance and between all variables of spinal mobility and balance. Regression analyses revealed that TMS explains between 1-33% of total variance of the respective balance parameters. Findings indicate that TMS is related to measures of steady-state balance which may imply that TMS promoting exercises should be integrated in strength training for seniors. KW - elderly KW - core KW - gait KW - postural balance KW - force KW - physical performance Y1 - 2014 U6 - https://doi.org/10.1123/JAPA.2013-0108 SN - 1063-8652 SN - 1543-267X VL - 22 IS - 4 SP - 490 EP - 498 PB - Human Kinetics Publ. CY - Champaign ER - TY - JOUR A1 - Mühlbauer, Thomas A1 - Besemer, Carmen A1 - Wehrle, Anja A1 - Gollhofer, Albert A1 - Granacher, Urs T1 - Relationship between strength; balance and mobility in children aged 7-10 years JF - Gait & posture N2 - The purpose of this study was to investigate the association between variables of lower extremity muscle strength, balance, and mobility assessed under various task conditions. Twenty-one healthy children (mean age: 9 +/- 1 years) were tested for their isometric and dynamic strength as well as for their steady-state, proactive, and reactive balance and mobility. Balance and mobility tests were conducted under single and dual task conditions. Significant positive correlations were detected between measures of isometric and dynamic leg muscle strength. Hardly any significant associations were observed between variables of strength and balance/mobility and between measures of steady-state, proactive, and reactive balance. Additionally, no significant correlations were detected between balance/mobility tests performed under single and dual task conditions. The predominately non-significant correlations between different balance components and mobility imply that balance and mobility performance is task specific. Further, strength and balance/mobility as well as balance under single and dual task conditions seem to be independent of each other and may have to be tested and trained complementarily. KW - Steady-state balance KW - Proactive/reactive balance KW - Maximal isometric force KW - Jumping height KW - Single/dual tasking KW - Cognitive/motor interference Y1 - 2013 U6 - https://doi.org/10.1016/j.gaitpost.2012.06.022 SN - 0966-6362 VL - 37 IS - 1 SP - 108 EP - 112 PB - Elsevier CY - Clare ER - TY - JOUR A1 - Mühlbauer, Thomas A1 - Besemer, Carmen A1 - Wehrle, Anja A1 - Gollhofer, Albert A1 - Granacher, Urs T1 - Relationship between strength, power and balance performance in seniors JF - Gerontology N2 - Background: Deficits in strength, power and balance represent important intrinsic risk factors for falls in seniors. Objective: The purpose of this study was to investigate the relationship between variables of lower extremity muscle strength/power and balance, assessed under various task conditions. Methods: Twenty-four healthy and physically active older adults (mean age: 70 8 5 years) were tested for their isometric strength (i.e. maximal isometric force of the leg extensors) and muscle power (i.e. countermovement jump height and power) as well as for their steady-state (i.e. unperturbed standing, 10-meter walk), proactive (i.e. Timed Up & Go test, Functional Reach Test) and reactive (i.e. perturbed standing) balance. Balance tests were conducted under single (i.e. standing or walking alone) and dual task conditions (i.e. standing or walking plus cognitive and motor interference task). Results: Significant positive correlations were found between measures of isometric strength and muscle power of the lower extremities (r values ranged between 0.608 and 0.720, p < 0.01). Hardly any significant associations were found between variables of strength, power and balance (i.e. no significant association in 20 out of 21 cases). Additionally, no significant correlations were found between measures of steady-state, proactive and reactive balance or balance tests performed under single and dual task conditions (all p > 0.05). Conclusion: The predominately nonsignificant correlations between different types of balance imply that balance performance is task specific in healthy and physically active seniors. Further, strength, power and balance as well as balance under single and dual task conditions seem to be independent of each other and may have to be tested and trained complementarily. KW - Steady-state balance KW - Proactive/reactive balance KW - Force production KW - Single/dual tasking KW - Cognitive/motor interference Y1 - 2012 U6 - https://doi.org/10.1159/000341614 SN - 0304-324X VL - 58 IS - 6 SP - 504 EP - 512 PB - Karger CY - Basel ER - TY - JOUR A1 - Golle, Kathleen A1 - Mühlbauer, Thomas A1 - Wick, Ditmar A1 - Granacher, Urs T1 - Physical Fitness Percentiles of German Children Aged 9–12 Years BT - findings from a Longitudinal Study JF - PLoS ONE N2 - Background Generating percentile values is helpful for the identification of children with specific fitness characteristics (i.e., low or high fitness level) to set appropriate fitness goals (i.e., fitness/health promotion and/or long-term youth athlete development). Thus, the aim of this longitudinal study was to assess physical fitness development in healthy children aged 9–12 years and to compute sex- and age-specific percentile values. Methods Two-hundred and forty children (88 girls, 152 boys) participated in this study and were tested for their physical fitness. Physical fitness was assessed using the 50-m sprint test (i.e., speed), the 1-kg ball push test, the triple hop test (i.e., upper- and lower- extremity muscular power), the stand-and-reach test (i.e., flexibility), the star run test (i.e., agility), and the 9-min run test (i.e., endurance). Age- and sex-specific percentile values (i.e., P10 to P90) were generated using the Lambda, Mu, and Sigma method. Adjusted (for change in body weight, height, and baseline performance) age- and sex-differences as well as the interactions thereof were expressed by calculating effect sizes (Cohen’s d). Results Significant main effects of Age were detected for all physical fitness tests (d = 0.40–1.34), whereas significant main effects of Sex were found for upper-extremity muscular power (d = 0.55), flexibility (d = 0.81), agility (d = 0.44), and endurance (d = 0.32) only. Further, significant Sex by Age interactions were observed for upper-extremity muscular power (d = 0.36), flexibility (d = 0.61), and agility (d = 0.27) in favor of girls. Both, linear and curvilinear shaped curves were found for percentile values across the fitness tests. Accelerated (curvilinear) improvements were observed for upper-extremity muscular power (boys: 10–11 yrs; girls: 9–11 yrs), agility (boys: 9–10 yrs; girls: 9–11 yrs), and endurance (boys: 9–10 yrs; girls: 9–10 yrs). Tabulated percentiles for the 9-min run test indicated that running distances between 1,407–1,507 m, 1,479–1,597 m, 1,423–1,654 m, and 1,433–1,666 m in 9- to 12-year-old boys and 1,262–1,362 m, 1,329–1,434 m, 1,392–1,501 m, and 1,415–1,526 m in 9- to 12-year-old girls correspond to a “medium” fitness level (i.e., P40 to P60) in this population. Conclusions The observed differences in physical fitness development between boys and girls illustrate that age- and sex-specific maturational processes might have an impact on the fitness status of healthy children. Our statistical analyses revealed linear (e.g., lower-extremity muscular power) and curvilinear (e.g., agility) models of fitness improvement with age which is indicative of timed and capacity-specific fitness development pattern during childhood. Lastly, the provided age- and sex-specific percentile values can be used by coaches for talent identification and by teachers for rating/grading of children’s motor performance. Y1 - 2015 U6 - https://doi.org/10.1371/journal.pone.0142393 SN - 1932-6203 VL - 10 IS - 11 PB - Public Library of Science CY - Lawrence, Kan. ER - TY - JOUR A1 - Golle, Kathleen A1 - Mühlbauer, Thomas A1 - Wick, Ditmar A1 - Granacher, Urs T1 - Physical Fitness Percentiles of German Children Aged 9-12 Years: Findings from a Longitudinal Study JF - PLoS one N2 - Background Generating percentile values is helpful for the identification of children with specific fitness characteristics (i. e., low or high fitness level) to set appropriate fitness goals (i. e., fitness/ health promotion and/or long-term youth athlete development). Thus, the aim of this longitudinal study was to assess physical fitness development in healthy children aged 9-12 years and to compute sex-and age-specific percentile values. Methods Two-hundred and forty children (88 girls, 152 boys) participated in this study and were tested for their physical fitness. Physical fitness was assessed using the 50-m sprint test (i. e., speed), the 1-kg ball push test, the triple hop test (i. e., upper-and lower-extremity muscular power), the stand-and-reach test (i. e., flexibility), the star run test (i. e., agility), and the 9-min run test (i. e., endurance). Age-and sex-specific percentile values (i. e., P-10 to P-90) were generated using the Lambda, Mu, and Sigma method. Adjusted (for change in body weight, height, and baseline performance) age-and sex-differences as well as the interactions thereof were expressed by calculating effect sizes (Cohen's d). Results Significant main effects of Age were detected for all physical fitness tests (d = 0.40-1.34), whereas significant main effects of Sex were found for upper-extremity muscular power (d = 0.55), flexibility (d = 0.81), agility (d = 0.44), and endurance (d = 0.32) only. Further, significant Sex by Age interactions were observed for upper-extremity muscular power (d = 0.36), flexibility (d = 0.61), and agility (d = 0.27) in favor of girls. Both, linear and curvilinear shaped curves were found for percentile values across the fitness tests. Accelerated (curvilinear) improvements were observed for upper-extremity muscular power (boys: 10-11 yrs; girls: 9-11 yrs), agility (boys: 9-10 yrs; girls: 9-11 yrs), and endurance (boys: 9-10 yrs; girls: 9-10 yrs). Tabulated percentiles for the 9-min run test indicated that running distances between 1,407-1,507 m, 1,479-1,597 m, 1,423-1,654 m, and 1,433-1,666 m in 9-to 12-year-old boys and 1,262-1,362 m, 1,329-1,434 m, 1,392-1,501 m, and 1,415-1,526 m in 9-to 12-year-old girls correspond to a "medium" fitness level (i. e., P-40 to P-60) in this population. Conclusions The observed differences in physical fitness development between boys and girls illustrate that age- and sex-specific maturational processes might have an impact on the fitness status of healthy children. Our statistical analyses revealed linear (e. g., lower-extremity muscular power) and curvilinear (e. g., agility) models of fitness improvement with age which is indicative of timed and capacity-specific fitness development pattern during childhood. Lastly, the provided age-and sex-specific percentile values can be used by coaches for talent identification and by teachers for rating/ grading of children's motor performance. Y1 - 2015 U6 - https://doi.org/10.1371/journal.pone.0142393 SN - 1932-6203 VL - 10 IS - 11 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Mühlbauer, Thomas A1 - Mettler, Claude A1 - Roth, Ralf A1 - Granacher, Urs T1 - One-leg standing performance and muscle activity: Are there limb differences? JF - Journal of applied biomechanics N2 - The purpose of this study was to compare static balance performance and muscle activity during one-leg standing on the dominant and nondominant leg under various sensory conditions with increased levels of task difficulty. Thirty healthy young adults (age: 23 +/- 2 years) performed one-leg standing tests for 30 s under three sensory conditions (ie, eyes open/firm ground; eyes open/foam ground [elastic pad on top of the balance plate]; eyes closed/firm ground). Center of pressure displacements and activity of four lower leg muscles (ie, m. tibialis anterior [TA], m. soleus [SOL], m. gastrocnemius medialis [GAS], m. peroneus longus [PER]) were analyzed. An increase in sensory task difficulty resulted in deteriorated balance performance (P < .001, effect size [ES] = .57-2.54) and increased muscle activity (P < .001, ES = .50-1.11) for all but two muscles (ie, GAS, PER). However, regardless of the sensory condition, one-leg standing on the dominant as compared with the nondominant limb did not produce statistically significant differences in various balance (P > .05, ES = .06-.22) and electromyographic (P > .05, ES = .03-.13) measures. This indicates that the dominant and the nondominant leg can be used interchangeably during static one-leg balance testing in healthy young adults. KW - postural control KW - electromyography KW - sensory input KW - task difficulty Y1 - 2014 U6 - https://doi.org/10.1123/jab.2013-0230 SN - 1065-8483 SN - 1543-2688 VL - 30 IS - 3 SP - 407 EP - 414 PB - Human Kinetics Publ. CY - Champaign ER - TY - JOUR A1 - Prieske, Olaf A1 - Mühlbauer, Thomas A1 - Borde, Ron A1 - Gube, M. A1 - Bruhn, S. A1 - Behm, David G. A1 - Granacher, Urs T1 - Neuromuscular and athletic performance following core strength training in elite youth soccer: Role of instability JF - Learning and individual differences N2 - Cross-sectional studies revealed that inclusion of unstable elements in core-strengthening exercises produced increases in trunk muscle activity and thus potential extra stimuli to induce more pronounced performance enhancements in youth athletes. Thus, the purpose of the study was to investigate changes in neuromuscular and athletic performance following core strength training performed on unstable (CSTU) compared with stable surfaces (CSTS) in youth soccer players. Thirty-nine male elite soccer players (age: 17 +/- 1 years) were assigned to two groups performing a progressive core strength-training program for 9 weeks (2-3 times/week) in addition to regular in-season soccer training. CSTS group conducted core exercises on stable (i.e., floor, bench) and CSTU group on unstable (e.g., Thera-Band (R) Stability Trainer, Togu (c) Swiss ball) surfaces. Measurements included tests for assessing trunk muscle strength/activation, countermovement jump height, sprint time, agility time, and kicking performance. Statistical analysis revealed significant main effects of test (pre vs post) for trunk extensor strength (5%, P<0.05, d=0.86), 10-20-m sprint time (3%, P<0.05, d=2.56), and kicking performance (1%, P<0.01, d=1.28). No significant Groupxtest interactions were observed for any variable. In conclusion, trunk muscle strength, sprint, and kicking performance improved following CSTU and CSTS when conducted in combination with regular soccer training. KW - Elite sports KW - jumping KW - agility KW - sprint KW - ball speed KW - electromyography Y1 - 2016 U6 - https://doi.org/10.1111/sms.12403 SN - 0905-7188 SN - 1600-0838 VL - 26 SP - 48 EP - 56 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Mühlbauer, Thomas A1 - Kühnen, Matthias A1 - Granacher, Urs T1 - Inline skating for balance and strength promotion in children during physical education JF - Perceptual & motor skills N2 - Deficiencies in balance and strength are common in children and they may lead to injuries. This study investigated the effects of inline skating exercise on balance and strength performance in healthy children. Twenty 11-12-year-old children (8 girls, 12 boys) were assigned to an intervention (n = 10) or a control (n = 10) group. Participants in the intervention group underwent a 4-week inline skating program (2 times/week, 90 min. each) integrated in their physical education lessons. Balance and strength were measured using the Star Excursion Balance test and the countermovement jump test. As compared to the control group, the intervention group significantly improved balance (17-48%, Cohen's d = 0.00-1.49) and jump height (8%, Cohen's d = 0.48). In children, inline skating is a safe, feasible (90% adherence rate), and effective program that can be integrated in physical education lessons to promote balance and strength. Y1 - 2013 U6 - https://doi.org/10.2466/30.06.PMS.117x29z9 SN - 0031-5125 VL - 117 IS - 3 SP - 665 EP - 681 PB - Sage Publ. CY - Missoula ER - TY - JOUR A1 - Prieske, Olaf A1 - Mühlbauer, Thomas A1 - Müller, Steffen A1 - Krüger, Tom A1 - Kibele, Armin A1 - Behm, David G. A1 - Granacher, Urs T1 - Effects of surface instability on neuromuscular performance during drop jumps and landings JF - European journal of applied physiology N2 - The purpose of this study was to investigate the effects of surface instability on measures of performance and activity of leg and trunk muscles during drop jumps and landings. Drop jumps and landings were assessed on a force plate under stable and unstable (balance pad on top of the force plate) conditions. Performance measures (contact time, jump height, peak ground reaction force) and electromyographic (EMG) activity of leg and trunk muscles were tested in 27 subjects (age 23 +/- A 3 years) during different time intervals (preactivation phase, braking phase, push-off phase). The performance of drop jumps under unstable compared to stable conditions produced a decrease in jump height (9 %, p < 0.001, f = 0.92) and an increase in peak ground reaction force (5 %, p = 0.022, f = 0.72), and time for braking phase (12 %, p < 0.001, f = 1.25). When performing drop jumps on unstable compared to stable surfaces, muscle activity was reduced in the lower extremities during the preactivation, braking and push-off phases (11-25 %, p < 0.05, 0.48 a parts per thousand currency sign f a parts per thousand currency sign 1.23). Additionally, when landing on unstable compared to stable conditions, reduced lower limb muscle activities were observed during the preactivation phase (7-60 %, p < 0.05, 0.50 a parts per thousand currency sign f a parts per thousand currency sign 3.62). Trunk muscle activity did not significantly differ between the test conditions for both jumping and landing tasks. The present findings indicate that modified feedforward mechanisms in terms of lower leg muscle activities during the preactivation phase and/or possible alterations in leg muscle activity shortly after ground contact (i.e., braking phase) are responsible for performance decrements during jumping on unstable surfaces. KW - Stretch-shortening cycle KW - Trunk muscle strength KW - Jump height KW - Electromyography Y1 - 2013 U6 - https://doi.org/10.1007/s00421-013-2724-6 SN - 1439-6319 SN - 1439-6327 VL - 113 IS - 12 SP - 2943 EP - 2951 PB - Springer CY - New York ER - TY - JOUR A1 - Beurskens, Rainer A1 - Mühlbauer, Thomas A1 - Granacher, Urs A1 - Gollhofer, Albert A1 - Cardinale, Marco T1 - Effects of heavy-resistance strength and balance training on unilateral and bilateral leg strength performance in old adults JF - PLoS one N2 - The term “bilateral deficit” (BLD) has been used to describe a reduction in performance during bilateral contractions when compared to the sum of identical unilateral contractions. In old age, maximal isometric force production (MIF) decreases and BLD increases indicating the need for training interventions to mitigate this impact in seniors. In a cross-sectional approach, we examined age-related differences in MIF and BLD in young (age: 20–30 years) and old adults (age: >65 years). In addition, a randomized-controlled trial was conducted to investigate training-specific effects of resistance vs. balance training on MIF and BLD of the leg extensors in old adults. Subjects were randomly assigned to resistance training (n = 19), balance training (n = 14), or a control group (n = 20). Bilateral heavy-resistance training for the lower extremities was performed for 13 weeks (3 × / week) at 80% of the one repetition maximum. Balance training was conducted using predominately unilateral exercises on wobble boards, soft mats, and uneven surfaces for the same duration. Pre- and post-tests included uni- and bilateral measurements of maximal isometric leg extension force. At baseline, young subjects outperformed older adults in uni- and bilateral MIF (all p < .001; d = 2.61–3.37) and in measures of BLD (p < .001; d = 2.04). We also found significant increases in uni- and bilateral MIF after resistance training (all p < .001, d = 1.8-5.7) and balance training (all p < .05, d = 1.3-3.2). In addition, BLD decreased following resistance (p < .001, d = 3.4) and balance training (p < .001, d = 2.6). It can be concluded that both training regimens resulted in increased MIF and decreased BLD of the leg extensors (HRT-group more than BAL-group), almost reaching the levels of young adults. Y1 - 2015 U6 - https://doi.org/10.1371/journal.pone.0118535 SN - 1932-6203 PB - Public Library of Science CY - Lawrence, Kan. ER - TY - JOUR A1 - Beurskens, Rainer A1 - Gollhofer, Albert A1 - Mühlbauer, Thomas A1 - Cardinale, Marco A1 - Granacher, Urs T1 - Effects of Heavy-Resistance Strength and Balance Training on Unilateral and Bilateral Leg Strength Performance in Old Adults JF - PLoS one N2 - The term "bilateral deficit" (BLD) has been used to describe a reduction in performance during bilateral contractions when compared to the sum of identical unilateral contractions. In old age, maximal isometric force production (MIF) decreases and BLD increases indicating the need for training interventions to mitigate this impact in seniors. In a cross-sectional approach, we examined age-related differences in MIF and BLD in young (age: 20-30 years) and old adults (age: > 65 years). In addition, a randomized-controlled trial was conducted to investigate training-specific effects of resistance vs. balance training on MIF and BLD of the leg extensors in old adults. Subjects were randomly assigned to resistance training (n = 19), balance training (n = 14), or a control group (n = 20). Bilateral heavy-resistance training for the lower extremities was performed for 13 weeks (3 x /week) at 80% of the one repetition maximum. Balance training was conducted using predominately unilateral exercises on wobble boards, soft mats, and uneven surfaces for the same duration. Pre-and post-tests included uni-and bilateral measurements of maximal isometric leg extension force. At baseline, young subjects outperformed older adults in uni-and bilateral MIF (all p < .001; d = 2.61-3.37) and in measures of BLD (p < .001; d = 2.04). We also found significant increases in uni-and bilateral MIF after resistance training (all p < .001, d = 1.8-5.7) and balance training (all p < .05, d = 1.3-3.2). In addition, BLD decreased following resistance (p < .001, d = 3.4) and balance training (p < .001, d = 2.6). It can be concluded that both training regimens resulted in increased MIF and decreased BLD of the leg extensors (HRT-group more than BAL-group), almost reaching the levels of young adults. Y1 - 2015 U6 - https://doi.org/10.1371/journal.pone.0118535 SN - 1932-6203 VL - 10 IS - 2 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Granacher, Urs A1 - Schellbach, Jörg A1 - Klein, Katja A1 - Prieske, Olaf A1 - Baeyens, Jean-Pierre A1 - Mühlbauer, Thomas T1 - Effects of core strength training using stable versus unstable surfaces on physical fitness in adolescents BT - a randomized controlled trial JF - BMC sports science, medicine & rehabilitation N2 - Background It has been demonstrated that core strength training is an effective means to enhance trunk muscle strength (TMS) and proxies of physical fitness in youth. Of note, cross-sectional studies revealed that the inclusion of unstable elements in core strengthening exercises produced increases in trunk muscle activity and thus provide potential extra training stimuli for performance enhancement. Thus, utilizing unstable surfaces during core strength training may even produce larger performance gains. However, the effects of core strength training using unstable surfaces are unresolved in youth. This randomized controlled study specifically investigated the effects of core strength training performed on stable surfaces (CSTS) compared to unstable surfaces (CSTU) on physical fitness in school-aged children. Methods Twenty-seven (14 girls, 13 boys) healthy subjects (mean age: 14 ± 1 years, age range: 13–15 years) were randomly assigned to a CSTS (n = 13) or a CSTU (n = 14) group. Both training programs lasted 6 weeks (2 sessions/week) and included frontal, dorsal, and lateral core exercises. During CSTU, these exercises were conducted on unstable surfaces (e.g., TOGU© DYNAIR CUSSIONS, THERA-BAND© STABILITY TRAINER). Results Significant main effects of Time (pre vs. post) were observed for the TMS tests (8-22%, f = 0.47-0.76), the jumping sideways test (4-5%, f = 1.07), and the Y balance test (2-3%, f = 0.46-0.49). Trends towards significance were found for the standing long jump test (1-3%, f = 0.39) and the stand-and-reach test (0-2%, f = 0.39). We could not detect any significant main effects of Group. Significant Time x Group interactions were detected for the stand-and-reach test in favour of the CSTU group (2%, f = 0.54). Conclusions Core strength training resulted in significant increases in proxies of physical fitness in adolescents. However, CSTU as compared to CSTS had only limited additional effects (i.e., stand-and-reach test). Consequently, if the goal of training is to enhance physical fitness, then CSTU has limited advantages over CSTS. KW - Resistance training KW - Trunk muscle strength KW - Physical fitness Y1 - 2014 U6 - https://doi.org/10.1186/2052-1847-6-40 SN - 2052-1847 VL - 6 PB - BioMed Central CY - London ER - TY - JOUR A1 - Granacher, Urs A1 - Lacroix, Andre A1 - Mühlbauer, Thomas A1 - Röttger, Katrin A1 - Gollhofer, Albert T1 - Effects of core instability strength training on trunk muscle strength, spinal mobility, dynamic balance and functional mobility in older adults JF - Gerontology N2 - Background: Age-related postural misalignment, balance deficits and strength/power losses are associated with impaired functional mobility and an increased risk of falling in seniors. Core instability strength training (CIT) involves exercises that are challenging for both trunk muscles and postural control and may thus have the potential to induce benefits in trunk muscle strength, spinal mobility and balance performance. Objective: The objective was to investigate the effects of CIT on measures of trunk muscle strength, spinal mobility, dynamic balance and functional mobility in seniors. Methods: Thirty-two older adults were randomly assigned to an intervention group (INT; n = 16, aged 70.8 +/- 4.1 years) that conducted a 9-week progressive CIT or to a control group (n = 16, aged 70.2 +/- 4.5 years). Maximal isometric strength of the trunk flexors/extensors/lateral flexors (right, left)/rotators (right, left) as well as of spinal mobility in the sagittal and the coronal plane was measured before and after the intervention program. Dynamic balance (i.e. walking 10 m on an optoelectric walkway, the Functional Reach test) and functional mobility (Timed Up and Go test) were additionally tested. Results: Program compliance was excellent with participants of the INT group completing 92% of the training sessions. Significant group x test interactions were found for the maximal isometric strength of the trunk flexors (34%, p < 0.001), extensors (21%, p < 0.001), lateral flexors (right: 48%, p < 0.001; left: 53%, p < 0.001) and left rotators (42%, p < 0.001) in favor of the INT group. Further, training-related improvements were found for spinal mobility in the sagittal (11%, p < 0.001) and coronal plane (11%, p = 0.06) directions, for stride velocity (9%, p < 0.05), the coefficient of variation in stride velocity (31%, p < 0.05), the Functional Reach test (20%, p < 0.05) and the Timed Up and Go test (4%, p < 0.05) in favor of the INT group. Conclusion: CIT proved to be a feasible exercise program for seniors with a high adherence rate. Age-related deficits in measures of trunk muscle strength, spinal mobility, dynamic balance and functional mobility can be mitigated by CIT. This training regimen could be used as an adjunct or even alternative to traditional balance and/or resistance training. KW - Elderly KW - Gait KW - Muscle strength KW - Physical performance KW - Postural balance Y1 - 2013 U6 - https://doi.org/10.1159/000343152 SN - 0304-324X VL - 59 IS - 2 SP - 105 EP - 113 PB - Karger CY - Basel ER - TY - JOUR A1 - Mühlbauer, Thomas A1 - Stürchler, M. A1 - Granacher, Urs T1 - Effects of climbing on core strength and mobility in adults JF - International journal of sports medicine N2 - The objective of this study was to examine the impact of an indoor climbing training and detraining program on core/handgrip strength and trunk mobility in men and women. 28 young sedentary adults participated in this study and were assigned to an intervention (30+/-3 years) or a control (29+/-2 years) group. The intervention group participated in 8 weeks (2 times/week) of indoor climbing training, followed by 8 weeks of detraining. Tests included the measurement of maximal isometric strength (MIS) of the trunk flexors/extensors, the assessment of trunk mobility in the sagittal (SAP) and the coronal (CRP) plane as well as testing of handgrip strength. After training, significant improvements were observed in MIS of the trunk flexors/extensors (similar to 19-22 %, all p<0.01), in trunk mobility in SAP/CRP (similar to 14-19 %, all p<0.01), and in handgrip strength (similar to 5 %, p<0.01). During detraining, MIS (similar to 12-13 %, all p<0.01) and trunk mobility (similar to 7-10%, all p<0.01) deteriorated significantly, whereas handgrip strength remained. This indoor climbing training program conducted in sedentary adults proved to be feasible (i.e., attendance rate of 89.4%) and effective. It is suggested that indoor climbing should be permanently conducted to maintain the observed improvements in core muscle strength and trunk mobility. KW - intervention KW - detraining KW - young adults KW - sedentary Y1 - 2012 U6 - https://doi.org/10.1055/s-0031-1301312 SN - 0172-4622 VL - 33 IS - 6 SP - 445 EP - 451 PB - Thieme CY - Stuttgart ER -