@misc{BeurskensMuehlbauerGranacher2015,
  author    = {Beurskens, Rainer and M{\"u}hlbauer, Thomas and Granacher, Urs},
  title     = {Association of dual-task walking performance and leg muscle quality in healthy children},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-75100},
  pages     = {7},
  year      = {2015},
  abstract  = {Background Previous literature mainly introduced cognitive functions to explain performance decrements in dual-task walking, i.e., changes in dual-task locomotion are attributed to limited cognitive information processing capacities. In this study, we enlarge existing literature and investigate whether leg muscular capacity plays an additional role in children's dual-task walking performance. Methods To this end, we had prepubescent children (mean age: 8.7 ± 0.5 years, age range: 7-9 years) walk in single task (ST) and while concurrently conducting an arithmetic subtraction task (DT). Additionally, leg lean tissue mass was assessed. Results Findings show that both, boys and girls, significantly decrease their gait velocity (f = 0.73), stride length (f = 0.62) and cadence (f = 0.68) and increase the variability thereof (f = 0.20-0.63) during DT compared to ST. Furthermore, stepwise regressions indicate that leg lean tissue mass is closely associated with step time and the variability thereof during DT (R2 = 0.44, p = 0.009). These associations between gait measures and leg lean tissue mass could not be observed for ST (R2 = 0.17, p = 0.19). Conclusion We were able to show a potential link between leg muscular capacities and DT walking performance in children. We interpret these findings as evidence that higher leg muscle mass in children may mitigate the impact of a cognitive interference task on DT walking performance by inducing enhanced gait stability.},
  language  = {en}
}
@article{BeurskensMuehlbauerGranacher2015,
  author    = {Beurskens, Rainer and M{\"u}hlbauer, Thomas and Granacher, Urs},
  title     = {Association of dual-task walking performance and leg muscle quality in healthy children},
  series = {BMC pediatrics},
  volume    = {15},
  journal   = {BMC pediatrics},
  number    = {2},
  publisher = {BioMed Central},
  address   = {London},
  issn      = {1471-2431},
  doi       = {10.1186/s12887-015-0317-8},
  year      = {2015},
  abstract  = {Background Previous literature mainly introduced cognitive functions to explain performance decrements in dual-task walking, i.e., changes in dual-task locomotion are attributed to limited cognitive information processing capacities. In this study, we enlarge existing literature and investigate whether leg muscular capacity plays an additional role in children's dual-task walking performance. Methods To this end, we had prepubescent children (mean age: 8.7 ± 0.5 years, age range: 7-9 years) walk in single task (ST) and while concurrently conducting an arithmetic subtraction task (DT). Additionally, leg lean tissue mass was assessed. Results Findings show that both, boys and girls, significantly decrease their gait velocity (f = 0.73), stride length (f = 0.62) and cadence (f = 0.68) and increase the variability thereof (f = 0.20-0.63) during DT compared to ST. Furthermore, stepwise regressions indicate that leg lean tissue mass is closely associated with step time and the variability thereof during DT (R2 = 0.44, p = 0.009). These associations between gait measures and leg lean tissue mass could not be observed for ST (R2 = 0.17, p = 0.19). Conclusion We were able to show a potential link between leg muscular capacities and DT walking performance in children. We interpret these findings as evidence that higher leg muscle mass in children may mitigate the impact of a cognitive interference task on DT walking performance by inducing enhanced gait stability.},
  language  = {en}
}
@misc{GolleMuehlbauerWicketal.2015,
  author    = {Golle, Kathleen and M{\"u}hlbauer, Thomas and Wick, Ditmar and Granacher, Urs},
  title     = {Physical Fitness Percentiles of German Children Aged 9-12 Years},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-86613},
  year      = {2015},
  abstract  = {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.},
  language  = {en}
}
@misc{BeurskensMuehlbauerGranacheretal.2015,
  author    = {Beurskens, Rainer and M{\"u}hlbauer, Thomas and Granacher, Urs and Gollhofer, Albert and Cardinale, Marco},
  title     = {Effects of heavy-resistance strength and balance training on unilateral and bilateral leg strength performance in old adults},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-73448},
  pages     = {13},
  year      = {2015},
  abstract  = {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.},
  language  = {en}
}
@article{GolleMuehlbauerWicketal.2015,
  author    = {Golle, Kathleen and M{\"u}hlbauer, Thomas and Wick, Ditmar and Granacher, Urs},
  title     = {Physical Fitness Percentiles of German Children Aged 9-12 Years},
  series = {PLoS ONE},
  volume    = {10},
  journal   = {PLoS ONE},
  number    = {11},
  publisher = {Public Library of Science},
  address   = {Lawrence, Kan.},
  issn      = {1932-6203},
  doi       = {10.1371/journal.pone.0142393},
  year      = {2015},
  abstract  = {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.},
  language  = {en}
}
@article{BeurskensMuehlbauerGranacheretal.2015,
  author    = {Beurskens, Rainer and M{\"u}hlbauer, Thomas and Granacher, Urs and Gollhofer, Albert and Cardinale, Marco},
  title     = {Effects of heavy-resistance strength and balance training on unilateral and bilateral leg strength performance in old adults},
  series = {PLoS one},
  journal   = {PLoS one},
  publisher = {Public Library of Science},
  address   = {Lawrence, Kan.},
  issn      = {1932-6203},
  doi       = {10.1371/journal.pone.0118535},
  pages     = {13},
  year      = {2015},
  abstract  = {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.},
  language  = {en}
}
@misc{GranacherHortobagyi2015,
  author    = {Granacher, Urs and Hortob{\´a}gyi, Tibor},
  title     = {Exercise to improve mobility in healthy aging},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {897},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-43241},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-432419},
  pages     = {4},
  year      = {2015},
  language  = {en}
}
@misc{KibeleGranacherMuehlbaueretal.2015,
  author    = {Kibele, Armin and Granacher, Urs and M{\"u}hlbauer, Thomas and Behm, David George},
  title     = {Stable, Unstable, and Metastable States of Equilibrium: Definitions and Applications to Human Movement},
  series = {Journal of sports science \& medicine},
  volume    = {14},
  journal   = {Journal of sports science \& medicine},
  number    = {4},
  publisher = {Department of Sports Medicine, Medical Faculty of Uludag University},
  address   = {Bursa},
  issn      = {1303-2968},
  pages     = {885 -- 887},
  year      = {2015},
  language  = {en}
}
@article{HortobagyiLesinskiGaebleretal.2015,
  author    = {Hortob{\´a}gyi, Tibor and Lesinski, Melanie and G{\"a}bler, Martijn and VanSwearingen, Jessie M. and Malatesta, Davide and Granacher, Urs},
  title     = {Effects of three types of exercise interventions on healthy old adults' gait speed},
  series = {Sports medicine},
  volume    = {45},
  journal   = {Sports medicine},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1179-2035},
  doi       = {10.1007/s40279-015-0371-2},
  pages     = {1627 -- 1643},
  year      = {2015},
  abstract  = {Background: Habitual walking speed predicts many clinical conditions later in life, but it declines with age. However, which particular exercise intervention can minimize the age-related gait speed loss is unclear. Purpose: Our objective was to determine the effects of strength, power, coordination, and multimodal exercise training on healthy old adults' habitual and fast gait speed. Methods: We performed a computerized systematic literature search in PubMed and Web of Knowledge from January 1984 up to December 2014. Search terms included 'Resistance training', 'power training', 'coordination training', 'multimodal training', and 'gait speed (outcome term). Inclusion criteria were articles available in full text, publication period over past 30 years, human species, journal articles, clinical trials, randomized controlled trials, English as publication language, and subject age C65 years. The methodological quality of all eligible intervention studies was assessed using the Physiotherapy Evidence Database (PEDro) scale. We computed weighted average standardized mean differences of the intervention-induced adaptations in gait speed using a random-effects model and tested for overall and individual intervention effects relative to no-exercise controls. Results: A total of 42 studies (mean PEDro score of 5.0 +/- 1.2) were included in the analyses (2495 healthy old adults; age 74.2 years [64.4-82.7]; body mass 69.9 +/- 4.9 kg, height 1.64 +/- 0.05 m, body mass index 26.4 +/- 1.9 kg/m(2), and gait speed 1.22 +/- 0.18 m/s). The search identified only one power training study, therefore the subsequent analyses focused only on the effects of resistance, coordination, and multimodal training on gait speed. The three types of intervention improved gait speed in the three experimental groups combined (n = 1297) by 0.10 m/s (+/- 0.12) or 8.4 \% (+/- 9.7), with a large effect size (ES) of 0.84. Resistance (24 studies; n = 613; 0.11 m/s; 9.3 \%; ES: 0.84), coordination (eight studies, n = 198; 0.09 m/s; 7.6 \%; ES: 0.76), and multimodal training (19 studies; n = 486; 0.09 m/s; 8.4 \%, ES: 0.86) increased gait speed statistically and similarly. Conclusions: Commonly used exercise interventions can functionally and clinically increase habitual and fast gait speed and help slow the loss of gait speed or delay its onset.},
  language  = {en}
}
@misc{LesinskiHortobagyiMuehlbaueretal.2015,
  author    = {Lesinski, Melanie and Hortobagyi, Tibor and M{\"u}hlbauer, Thomas and Gollhofer, Albert and Granacher, Urs},
  title     = {Dose-Response Relationships of Balance Training in Healthy Young Adults: A Systematic Review and Meta-Analysis},
  series = {Sports medicine},
  volume    = {45},
  journal   = {Sports medicine},
  number    = {4},
  publisher = {Springer},
  address   = {Northcote},
  issn      = {0112-1642},
  doi       = {10.1007/s40279-014-0284-5},
  pages     = {557 -- 576},
  year      = {2015},
  abstract  = {Background Balance training (BT) has been used for the promotion of balance and sports-related skills as well as for prevention and rehabilitation of lower extremity sport injuries. However, evidence-based dose-response relationships in BT parameters have not yet been established. Objective The objective of this systematic literature review and meta-analysis was to determine dose-response relationships in BT parameters that lead to improvements in balance in young healthy adults with different training status. Data Sources A computerized systematic literature search was performed in the electronic databases PubMed, Web of Knowledge, and SPORTDiscus from January 1984 up to May 2014 to capture all articles related to BT in young healthy adults. Study Eligibility Criteria A systematic approach was used to evaluate the 596 articles identified for initial review. Only randomized controlled studies were included if they investigated BT in young healthy adults (16-40 years) and tested at least one behavioral balance performance outcome. In total, 25 studies met the inclusion criteria for review. Study Appraisal and Synthesis Methods Studies were evaluated using the physiotherapy evidence database (PEDro) scale. Within-subject effect sizes (ESdw) and between-subject effect sizes (ESdb) were calculated. The included studies were coded for the following criteria: training status (elite athletes, sub-elite athletes, recreational athletes, untrained subjects), training modalities (training period, frequency, volume, etc.), and balance outcome (test for the assessment of steady-state, proactive, and reactive balance). Results Mean ESdb demonstrated that BT is an effective means to improve steady-state (ESdb = 0.73) and proactive balance (ESdb = 0.92) in healthy young adults. Studies including elite athletes showed the largest effects (ESdb = 1.29) on measures of steady-state balance as compared with studies analyzing sub-elite athletes (ESdb = 0.32), recreational athletes (ESdb = 0.69), and untrained subjects (ESdb = 0.82). Our analyses regarding dose-response relationships in BT revealed that a training period of 11-12 weeks (ESdb = 1.09), a training frequency of three (mean ESdb = 0.72) or six (single ESdb = 1.84) sessions per week, at least 16-19 training sessions in total (ESdb = 1.12), a duration of 11-15 min for a single training session (ESdb = 1.11), four exercises per training session (ESdb = 1.29), two sets per exercise (ESdb = 1.63), and a duration of 21-40 s for a single BT exercise (ESdb = 1.06) is most effective in improving measures of steady-state balance. Due to a small number of studies, dose-response relationships of BT for measures of proactive and reactive balance could not be qualified. Limitations The present findings must be interpreted with caution because it is difficult to separate the impact of a single training modality (e.g., training frequency) from that of the others. Moreover, the quality of the included studies was rather limited, with a mean PEDro score of 5. Conclusions Our detailed analyses revealed effective BT parameters for the improvement of steady-state balance. Thus, practitioners and coaches are advised to consult the identified dose-response relationships of this systematic literature review and meta-analysis to implement effective BT protocols in clinical and sports-related contexts. However, further research of high methodological quality is needed to (1) determine dose-response relationships of BT for measures of proactive and reactive balance, (2) define effective sequencing protocols in BT (e.g., BT before or after a regular training session), (3) discern the effects of detraining, and (4) develop a feasible and effective method to regulate training intensity in BT.},
  language  = {en}
}