P Aagaard

University of Southern Denmark, Odense, South Denmark, Denmark

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Publications (243)579.18 Total impact

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    ABSTRACT: Life-long regular endurance exercise is known to counteract the deterioration of cardiovascular and metabolic function and overall mortality. Yet it remains unknown if life-long regular endurance exercise can influence the connective tissue accumulation of advanced glycation endproducts (AGEs) that is associated with aging and lifestyle-related diseases. We therefore examined two groups of healthy elderly men: 15 master athletes (64 ± 4 years) who had been engaged in life-long endurance running and 12 old untrained (66 ± 4 years) together with two groups of healthy young men; ten young athletes matched for running distance (26 ± 4 years), and 12 young untrained (24 ± 3 years). AGE cross-links (pentosidine) of the patellar tendon were measured biochemically, and in the skin, it was assessed by a fluorometric method. In addition, we determined mechanical properties and microstructure of the patellar tendon. Life-long regular endurance runners (master athletes) had a 21 % lower AGE cross-link density compared to old untrained. Furthermore, both master athletes and young athletes displayed a thicker patellar tendon. These cross-sectional data suggest that life-long regular endurance running can partly counteract the aging process in connective tissue by reducing age-related accumulation of AGEs. This may not only benefit skin and tendon but also other long-lived protein tissues in the body. Furthermore, it appears that endurance running yields tendon tissue hypertrophy that may serve to lower the stress on the tendon and thereby reduce the risk of injury.
    Age (Dordrecht, Netherlands). 08/2014; 36(4):9665.
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    ABSTRACT: Modern team handball match-play imposes substantial physical and technical demands on elite players. However, only limited knowledge seems to exist about the specific working requirements in elite team handball. Thus, the purpose of the present study was to examine the physical demands imposed on male elite team handball players in relation to playing position and body anthropometry.Based on continuous video recording of individual players during elite team handball match-play (62 tournament games, ∼ 4 players per game), computerized technical match analysis was performed in male elite team handball players along with anthropometric measurements over a six season time span. Technical match activities were distributed in 6 major types of playing actions (shots, breakthroughs, fast breaks, tackles, technical errors and defense errors) and further divided into various subcategories (e.g. hard or light tackles, type of shot, clapings, screenings and blockings).Players showed 36.9±13.1 (group means±SD) high-intense technical playing actions per match with a mean total effective playing time of 53.85±5.87 min. In offense, each player performed 6.0±5.2 fast breaks, received 34.5±21.3 tackles in total and performed in defense 3.7±3.5 blockings and 3.9±3.0 claspings and 5.8±3.6 hard tackles. Wing players (84.5±5.8 kg, 184.9±5.7 cm) were less heavy and smaller (p<0.001) than backcourt players (94.7±7.1 kg, 191.9±5.4 cm) and pivots (99.4±6.2 kg, 194.8±3.6 cm).In conclusion, modern male elite team handball match-play is characterized by a high number of short-term, high-intense intermittent technical playing actions. Indications of technical fatigue were observed. Physical demands differed between playing positions with wing players performing more fast breaks and less physical confrontations with opponent players than backcourt players and pivots. Body anthropometry appeared to have an important influence on playing performance, since highly related to playing positions. The present observations suggest that male elite team handball players should implement more position-specific training regimens, while also focusing on anaerobic training and strength training.
    Journal of strength and conditioning research / National Strength & Conditioning Association. 06/2014;
  • L B Michalsik, P Aagaard
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    ABSTRACT: The aim of the present study was to examine differences in the physical demands imposed on male vs. female adult elite team handball players during match--play.
    The Journal of sports medicine and physical fitness. 06/2014;
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    ABSTRACT: The neuromuscular adaptations in response to muscle stretch training have not been clearly described. In the present study, changes in muscle (at fascicular and whole muscle levels) and tendon mechanics, muscle activity and spinal motoneuron excitability were examined during standardized plantar flexor stretches after 3 wk of twice-daily stretch training (4×30-s). No changes were observed in a non-exercising control group (N=9), however stretch training elicited a 19.9% increase in dorsiflexion range of motion (ROM) and 28% increase in passive joint moment at end ROM (N=12). Only a trend toward a decrease in passive plantar flexor moment during stretch (-9.9%, p=0.15) was observed and no changes in EMG amplitudes during or at end ROM were detected. Decreases in Hmax:Mmax (tibial nerve stimulation) were observed at plantar flexed (gastrocnemius medialis and soleus) and neutral (soleus only) joint angles, but not with the ankle dorsiflexed. Muscle and fascicle strain increased (12 vs. 23%) along with a decrease in muscle stiffness (-18%) during stretch to a constant target joint angle. Muscle length at end ROM increased (13%) without a change in fascicle length, fascicle rotation, tendon elongation or tendon stiffness following training. A lack of change in MVC moment and RFD at any joint angle was taken to indicate a lack of change in series compliance of the muscle-tendon unit. Thus, increases in end ROM were underpinned by increases in maximum tolerable passive joint moment ('stretch tolerance') and both muscle and fascicle elongation rather than changes in volitional muscle activation or motoneuron pool excitability.
    Journal of Applied Physiology 06/2014; · 3.48 Impact Factor
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    ABSTRACT: The effects of 16 weeks of football or strength training on performance and functional ability were investigated in 26 (68.2 ± 3.2 years) untrained men randomized into a football (FG; n = 9), a strength training (ST; n = 9), or a control group (CO; n = 8). FG and ST trained 1.6 ± 0.1 and 1.5 ± 0.1 times per week, respectively, with higher (P < 0.05) average heart rate (HR) (∼ 140 vs 100 bpm) and time >90%HRmax (17 vs 0%) in FG than ST, and lower (P < 0.05) peak blood lactate in FG than ST (7.2 ± 0.9 vs 10.5 ± 0.6 mmol/L). After the intervention period (IP), VO2 max (15%; P < 0.001), cycle time to exhaustion (7%; P < 0.05), and Yo-Yo Intermittent Endurance Level 1 performance (43%; P < 0.01) were improved in FG, but unchanged in ST and CO. HR during walking was 12% and 10% lower (P < 0.05) in FG and ST, respectively, after IP. After IP, HR and blood lactate during jogging were 7% (P < 0.05) and 30% lower (P < 0.001) in FG, but unchanged in ST and CO. Sit-to-stand performance was improved (P < 0.01) by 29% in FG and 26% in ST, but not in CO. In conclusion, football and strength training for old men improves functional ability and physiological response to submaximal exercise, while football additionally elevates maximal aerobic fitness and exhaustive exercise performance.
    Scandinavian Journal of Medicine and Science in Sports 06/2014; · 3.21 Impact Factor
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    ABSTRACT: The prevalence and consequences of musculoskeletal pain is considerable among healthcare workers, allegedly due to high physical work demands of healthcare work. Previous investigations have shown promising results of physical exercise for relieving pain among different occupational groups, but the question remains whether such physical exercise should be performed at the workplace or conducted as home-based exercise. Performing physical exercise at the workplace together with colleagues may be more motivating for some employees and thus increase adherence. On the other hand, physical exercise performed during working hours at the workplace may be costly for the employers in terms of time spend. Thus, it seems relevant to compare the efficacy of workplace- versus home-based training on musculoskeletal pain. This study is intended to investigate the effect of workplace-based versus home-based physical exercise on musculoskeletal pain among healthcare workers.Methods/design: This study was designed as a cluster randomized controlled trial performed at 3 hospitals in Copenhagen, Denmark. Clusters are hospital departments and hospital units. Cluster randomization was chosen to increase adherence and avoid contamination between interventions. Two hundred healthcare workers from 18 departments located at three different hospitals is allocated to 10 weeks of 1) workplace based physical exercise performed during working hours (using kettlebells, elastic bands and exercise balls) for 5 x 10 minutes per week and up to 5 group-based coaching sessions, or 2) home based physical exercise performed during leisure time (using elastic bands and body weight exercises) for 5 x 10 minutes per week. Both intervention groups will also receive ergonomic instructions on patient handling and use of lifting aides etc. Inclusion criteria are female healthcare workers working at a hospital. Average pain intensity (VAS scale 0-10) of the back, neck and shoulder (primary outcome) and physical exertion during work, social capital and work ability (secondary outcomes) is assessed at baseline and 10-week follow-up. Further, postural balance and mechanical muscle function is assessed during clinical examination at baseline and follow-up. This cluster randomized trial will investigate the change in self-rated average pain intensity in the back, neck and shoulder after either 10 weeks of physical exercise at the workplace or at home.Trial registration: ClinicalTrials.gov (NCT01921764).
    BMC Musculoskeletal Disorders 04/2014; 15(1):119. · 1.88 Impact Factor
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    ABSTRACT: Biomechanical investigations of sports-specific movements may yield information on which measures could be most efficient for prevention of Anterior Cruciate Ligament (ACL) injuries. High knee valgus moments have been related to increased risk of ACL injury, but further knowledge is needed on how hip strength and hip joint control may influence valgus moments during sidecutting. To investigate the relation between isolated hip muscle strength, hip kinematics and knee valgus moments. Cross-sectional. Biomechanical laboratory. Youth elite level. 97 female handball and football players aged 15-19 yrs selected for the youth national teams were recruited. Maximal isometric hip strength was measured during hip abduction, hip extension and hip external rotation [N/kg BM]) by a handheld dynamometer. A standardized sidecutting was performed by each player and hip joint kinematics were measured at initial contact (IC) along with identification of the peak knee joint valgus moment in the contact phase. Regression analysis was used to determine which of the measured parameters would affect knee valgus moment, and as such represent potential risk factors that should be targeted in future prophylactic training regimes. No relation between maximal isometric hip muscle strength and knee valgus moment was found. Regression analysis showed weak but significant effect of hip internal rotation at IC and hip abduction at IC on knee valgus moment (r(2)=.33, P<.001, β-coefficients=0.49 and 0.35 for hip internal rotation and hip abduction, respectively). The study shows that isometric hip muscle strength did not relate to peak knee valgus moment in young female elite handball and football players. However, increased hip internal rotation and increased hip abduction appeared to negatively influence the magnitude of knee valgus moment during sidecutting, and thus potentially increase the risk of ACL-injury.
    British journal of sports medicine 04/2014; 48(7):566. · 3.67 Impact Factor
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    ABSTRACT: The most commonly used graft in ACL-reconstructions is harvested from the semitendinosus muscle (ST) which causes atrophy and reduced muscle strength in the hamstrings. As the ST serves as an important ACL agonist, exercises that causes high levels of ST muscle activity after ACL-reconstruction, is of great interest to prevent re-rupture of the ACL. The purpose of the present study was to examine the level of neuromuscular hamstring muscle activity during two commonly used strength exercises, the two hand Kettlebell Swing (KS) and the Nordic Hamstring (NH), in previously ACL-reconstructed female athletes. Cross-sectional study. Biomechanical laboratory. Recruitment ongoing - the study is planned to include 20 participants. Preliminary data from five female athletes (age 28±7 yrs) with a total of 6 ACL-reconstructed knees are presented. In all cases, ST tendon was used as graft. The time between surgery and testing was 52±47months. Ten consecutive KS's were performed corresponding to a maximal load (12-16 kg) where correct technique was maintained. Additional, five consecutive NH curls were executed. Muscle activity for the hamstring muscles was obtained during the exercise evaluation and during hamstring MVC. Peak EMG of the medial (ST) and lateral (BF) hamstring during KS and NH was normalized to peak EMG amplitude during MVC. The exercise evaluation showed a significantly higher peak ST EMG activity during KS than NH (91±23% vs. 63±23%, respectively), P=.011. No difference was observed in peak BF EMG activity between exercises (82±30% vs. 66±36%, respectively), P=.125. The present finding suggests that the KB exercise could be introduced in rehabilitation when aiming at enhanced ability to recruit ST during forceful movements. However, to avoid adverse effects in the early phase of rehabilitation, caution must be taken when introducing high-intensity training among ACL reconstructed patients.
    British journal of sports medicine 04/2014; 48(7):623. · 3.67 Impact Factor
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    ABSTRACT: Chronic pain and disability of the arm, shoulder, and hand severely affect labor market participation. Ergonomic training and education is the default strategy to reduce physical exposure and thereby prevent aggravation of pain. An alternative strategy could be to increase physical capacity of the worker by physical conditioning. To investigate the effect of 2 contrasting interventions, conventional ergonomic training (usual care) versus resistance training, on pain and disability in individuals with upper limb chronic pain exposed to highly repetitive and forceful manual work. Examiner-blinded, parallel-group randomized controlled trial with allocation concealment. Slaughterhouses located in Denmark, Europe. Sixty-six adults with chronic pain in the shoulder, elbow/forearm, or hand/wrist and work disability were randomly allocated to 10 weeks of specific resistance training for the shoulder, arm, and hand muscles for 3 x 10 minutes per week, or ergonomic training and education (usual care control group). Pain intensity (average of shoulder, arm, and hand, scale 0 - 10) was the primary outcome, and disability (Work module of DASH questionnaire) as well as isometric shoulder and wrist muscle strength were secondary outcomes. Pain intensity, disability, and muscle strength improved more following resistance training than usual care (P < 0.001, < 0.05, < 0.0001, respectively). Pain intensity decreased by 1.5 points (95% confidence interval -2.0 to -0.9) following resistance training compared with usual care, corresponding to an effect size of 0.91 (Cohen's d). Blinding of participants is not possible in behavioral interventions. However, at baseline outcome expectations of the 2 interventions were similar. Resistance training at the workplace results in clinical relevant improvements in pain, disability, and muscle strength in adults with upper limb chronic pain exposed to highly repetitive and forceful manual work. Trial registration: NCT01671267.
    Pain physician 03/2014; 17(2):145-54. · 10.72 Impact Factor
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    ABSTRACT: Several therapies have been used in the treatment of chronic low back pain, including various exercise strategies and spinal manipulative therapy. A common belief is that spinal motion changes in particular ways in direct response to specific interventions, such as exercise or spinal manipulation. The purpose of this study was to assess changes in lumbar region motion over 12 weeks by evaluating four motion parameters in the sagittal plane and two in the horizontal plane in LBP patients treated with either exercise therapy or spinal manipulation. Secondary analysis of a subset of participants from a randomized clinical trial. 199 study participants with low back pain of more than six weeks' duration who had spinal motion measures obtained before and after the period of intervention. Lumbar region spinal kinematics sampled using a six-degree-of-freedom instrumented spatial linkage system. Trained therapists collected regional lumbar spinal motion data at baseline and at 12 weeks follow up. The lumbar region spinal motion data were analyzed as a total cohort and relative to treatment modality (high-dose, supervised low-tech trunk exercise, spinal manipulative therapy, and a short course of home exercise and self-care advice). The study was supported by grants from Health Resources and Services Administration, Danish Agency for Science Technology and Innovation, Danish Chiropractors Research Foundation, and the University of Southern Denmark. No conflicts of interest. For the cohort as a whole, lumbar region motion parameters were altered over the 12-week period, except for the jerk index parameter. The group receiving spinal manipulation changed significantly in all, and the exercise groups in half, the motion parameters included in the analysis. The spinal manipulation group changed to a smoother motion pattern (reduced jerk index) while the exercise groups did not. This study provides evidence that spinal motion changes can occur in chronic low back pain patients over a 12-week period and that these changes are associated with the type of treatment.
    The spine journal: official journal of the North American Spine Society 03/2014; · 2.90 Impact Factor
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    ABSTRACT: Imbalance between work demands and individual resources can lead to musculoskeletal disorders and reduced work ability. The aim of this study was to evaluate the effect of two contrasting interventions on work ability among slaughterhouse workers with chronic pain and work disability. Sixty-six slaughterhouse workers with upper-limb chronic pain and work disability were randomly allocated to 10 weeks of either strength training for the shoulder, arm, and hand muscles (3 times per week, 10 minutes per session) or ergonomic training (usual care control group) from September to December 2012. The outcome measure was the change from baseline to 10-week follow-up in the work ability index (WAI). A priori hypothesis testing showed a group×time interaction for WAI (P<0.05). Compared with the ergonomic training group, WAI increased 2.3 [95% confidence interval (95% CI) 0.9-3.7] in the strength training group corresponding to a moderate effect size (Cohen's d 0.52). Within-group changes indicated that between-group differences were mainly caused by a reduction in WAI in the ergonomic group. Of the 7 items of WAI, item 2 (work ability in relation to the demands of the job) and item 7 (mental resources) increased following strength training compared with ergonomic training (P<0.05). Implementation of strength training at the workplace prevents deterioration of work ability among manual workers with chronic pain and disability exposed to forceful and repetitive job tasks. Thus, strength training performed at the workplace may in fact be regarded as a complex biopsychosocial intervention modality that reaches further than the specific physiological benefits of training per se.
    Scandinavian Journal of Work, Environment & Health 02/2014; · 3.10 Impact Factor
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    ABSTRACT: As aged individuals are frequently exposed to short-term disuse caused by disease or musculoskeletalinjury, it is important to understand how short-term disuse and subsequent retraining affects lower limb mechanical muscle function.The purpose of the present study was, therefore, to investigate the effect of 4 days of lower limb disuse followed by 7 days of active recovery on mechanical muscle functionof the knee extensors in young (24.3±0.9yrs,n=11) and old (67.2±1.0yrs, n=11) recreationally active healthy males.Slow and moderate dynamic muscle strength were assessed using isokinetic dynamometry (60 and 180 °.s-1, respectively) along with isometric muscle strength andrapid muscle force capacity examined as contractile rate of force development (RFD), Impulse, and relative RFD (rRFD) during the initial phase of contraction (100 mstime interval relative to onset of contraction). Prior to disuse, marked age-related differences (p<0.05) were observed in isometric and dynamic muscle strength (~35%) as well as in RFD and Impulse (~39%). Following disuse, young and old experienced comparable decrements (p<0.05) in isometric strength (~9%), slow dynamic strength (~13%), RFD and Impulse (~19%), whereas old only experienced decrements (p<0.05)in moderatedynamic strength (12%) and rRFD (~17%). Following recovery, all measures of mechanical muscle function were restored in youngcompared to pre-disuse values, while isometric, slow and moderate dynamic muscle strength remained suppressed (p<0.05) in old (~8%)along with a tendency to suppressed RFD100ms(p=0.068).In conclusion,4 daysof lower limb disuse led to marked decrements in knee extensor mechanical muscle function in both young and old individuals, yet with greater decrements observed in moderate dynamic strength and rapid muscle force capacity in old. While 7 days of recovery - including free ambulation, one test session and a single session of strength training -wassufficient to restore mechanical muscle functionin young individuals, old individuals appeared to have an impaired ability to fully recover as evidenced by suppressed values of isometric and dynamicmuscle strength and rapid muscle force capacity.
    Experimental Gerontology 01/2014; · 3.91 Impact Factor
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    ABSTRACT: As aged individuals are frequently exposed to short-term disuse caused by disease or musculoskeletalinjury, it is important to understand how short-term disuse and subsequent retraining affects lower limb mechanical muscle function.The purpose of the present study was, therefore, to investigate the effect of 4 days of lower limb disuse followed by 7 days of active recovery on mechanical muscle functionof the knee extensors in young (24.3±0.9yrs,n=11) and old (67.2±1.0yrs, n=11) recreationally active healthy males.Slow and moderate dynamic muscle strength were assessed using isokinetic dynamometry (60 and 180 °(.)s(-1), respectively) along with isometric muscle strength andrapid muscle force capacity examined as contractile rate of force development (RFD), Impulse, and relative RFD (rRFD) during the initial phase of contraction (100 mstime interval relative to onset of contraction). Prior to disuse, marked age-related differences (p<0.05) were observed in isometric and dynamic muscle strength (~35%) as well as in RFD and Impulse (~39%). Following disuse, young and old experienced comparable decrements (p<0.05) in isometric strength (~9%), slow dynamic strength (~13%), RFD and Impulse (~19%), whereas old only experienced decrements (p<0.05)in moderatedynamic strength (12%) and rRFD (~17%). Following recovery, all measures of mechanical muscle function were restored in youngcompared to pre-disuse values, while isometric, slow and moderate dynamic muscle strength remained suppressed (p<0.05) in old (~8%)along with a tendency to suppressed RFD100ms(p=0.068).In conclusion,4 daysof lower limb disuse led to marked decrements in knee extensor mechanical muscle function in both young and old individuals, yet with greater decrements observed in moderate dynamic strength and rapid muscle force capacity in old. While 7 days of recovery - including free ambulation, one test session and a single session of strength training -wassufficient to restore mechanical muscle functionin young individuals, old individuals appeared to have an impaired ability to fully recover as evidenced by suppressed values of isometric and dynamicmuscle strength and rapid muscle force capacity.
    Experimental gerontology 01/2014; · 3.34 Impact Factor
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    ABSTRACT: In military operations, declined physical capacity can endanger the life of soldiers. During special support and reconnaissance (SSR) missions, Special Forces soldiers sustain 1-2 weeks full-body horizontal immobilization, which impairs muscle strength and performance. Adequate muscle mass and strength are necessary in combat or evacuation situations, which prompt for improved understanding of muscle mass modulation during SSR missions. To explore the molecular regulation of myofiber size during a simulated SSR operation, nine male Special Forces soldiers were biopsied in m. vastus lateralis pre and post 8 days immobilizing restricted prone position. After immobilization, total mammalian target of rapamycin protein was reduced by 42% (P < 0.05), whereas total and phosphorylated protein levels of Akt, ribosomal protein S6k, 4E-BP1, and glycogen synthase kinase3β were unchanged. Messenger RNA (mRNA) levels of the atrogenes forkhead box O3 (FoxO3), atrogin1, and muscle ring finger protein1 (MuRF1) increased by 36%, 53%, and 71% (P < 0.01), MuRF1 protein by 51% (P = 0.05), whereas FoxO1 and peroxisome proliferator-activated receptor γ coactivator-1 β mRNAs decreased by 29% and 40% (P < 0.01). In conclusion, occupational immobilization in Special Forces soldiers led to modulations in molecular muscle mass regulators during 8 days prone SSR mission, which likely contribute to muscle loss observed in such operations. The present data expand our knowledge of human muscle mass regulation during short-term immobilization.
    Scandinavian Journal of Medicine and Science in Sports 01/2014; · 3.21 Impact Factor
  • L B Michalsik, K Madsen, P Aagaard
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    ABSTRACT: Aim: The aim of the present study was to examine the physical demands placed on male elite team handball (TH) players in relation to playing position. Methods: Male elite TH field players were evaluated during match-play over a six season time span using physiological measurements and by subsequent physical testing. Results: Mean heart rate and relative workload during match-play (n=41) were 163±5 beats·min-1 (group means±SD) and 70.9±6.0 % of VO2-max, respectively. Relative workload was lower (p<0.01) in the second half vs. the first (66.3±5.9 % vs. 75.4±5.6 % of VO2-max). Post-match blood lactate concentration was 4.8±1.9 mM (range: 2.8-10.8 mM). Mean fluid loss was 0.81±0.41 l pr. match. Mean VO2-max was 5.18±0.66 l O2·min-1 corresponding to 57.0±4.1 ml O2·min-1·kg-1. Mean total running distance in the Yo-Yo intermittent recovery test (level 2) was 895±184 m (range: 520-1360 m), which was greater in wing players (975±123 m) than backcourt players (897±108 m) and pivots (827±264 m) (p<0.05). Fastest 30-m sprint time was 4.09± 0.12 s (range: 3.87-4.28 s). The repeated sprint test (7 x 30-m) yielded a mean fatigue index of -8.1± 2.7 %. Maximal jumping height in "Jump and Reach" testing was 0.71±0.08 m (range: 0.61-0.86 m). Maximal ball throwing speed was observed using the set shot with 3-steps run-up (92.8±5.3 km·h-1, range: 75.8-108.2 km·h-1). Conclusions: Modern male elite TH imposes moderate-to-high demands on the aerobic energy system and high demands on the anaerobic energy systems during certain periods of the match. Indications of temporary fatigue and a subsequent decline in performance were observed, since the relative workload decreased both in the first and in the second half of the match. Physical profile differed between playing positions, where wing players covered a greater total distance in the Yo-Yo test and showed superior jumping performance and repeated sprint capacity than backcourt players and pivots.
    The Journal of sports medicine and physical fitness 01/2014; · 0.73 Impact Factor
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    ABSTRACT: Objective. Persistent weakness is a common problem after anterior cruciate ligament- (ACL-) reconstruction. This study investigated the effects of high-intensity (HRT) versus low-intensity (LRT) resistance training on leg extensor power and recovery of knee function after ACL-reconstruction. Methods. 31 males and 19 females were randomized to HRT (n = 24) or LRT (n = 26) from week 8-20 after ACL-reconstruction. Leg extensor power, joint laxity, and self-reported knee function were measured before and 7, 14, and 20 weeks after surgery. Hop tests were assessed before and after 20 weeks. Results. Power in the injured leg was 90% (95% CI 86-94%) of the noninjured leg, decreasing to 64% (95% CI 60-69%) 7 weeks after surgery. During the resistance training phase there was a significant group by time interaction for power (P = 0.020). Power was regained more with HRT compared to LRT at week 14 (84% versus 73% of noninjured leg, resp.; P = 0.027) and at week 20 (98% versus 83% of noninjured leg, resp.; P = 0.006) without adverse effects on joint laxity. No other between-group differences were found. Conclusion. High-intensity resistance training during rehabilitation after ACL-reconstruction can improve muscle power without adverse effects on joint laxity.
    BioMed Research International 01/2014; 2014:278512. · 2.71 Impact Factor
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    ABSTRACT: Background Context Several therapies have been used in the treatment of chronic low back pain, including various exercise strategies and spinal manipulative therapy. A common belief is that spinal motion changes in particular ways in direct response to specific interventions, such as exercise or spinal manipulation. Purpose The purpose of this study was to assess changes in lumbar region motion over 12 weeks by evaluating four motion parameters in the sagittal plane and two in the horizontal plane in LBP patients treated with either exercise therapy or spinal manipulation. Study Design/Setting Secondary analysis of a subset of participants from a randomized clinical trial. Patient Sample 199 study participants with low back pain of more than six weeks' duration who had spinal motion measures obtained before and after the period of intervention. Outcome Measures Lumbar region spinal kinematics sampled using a six-degree-of-freedom instrumented spatial linkage system. Methods Trained therapists collected regional lumbar spinal motion data at baseline and at 12 weeks follow up. The lumbar region spinal motion data were analyzed as a total cohort and relative to treatment modality (high-dose, supervised low-tech trunk exercise, spinal manipulative therapy, and a short course of home exercise and self-care advice). The study was supported by grants from Health Resources and Services Administration, Danish Agency for Science Technology and Innovation, Danish Chiropractors Research Foundation, and the University of Southern Denmark. No conflicts of interest. Results For the cohort as a whole, lumbar region motion parameters were altered over the 12-week period, except for the jerk index parameter. The group receiving spinal manipulation changed significantly in all, and the exercise groups in half, the motion parameters included in the analysis. The spinal manipulation group changed to a smoother motion pattern (reduced jerk index) while the exercise groups did not. Conclusion This study provides evidence that spinal motion changes can occur in chronic low back pain patients over a 12-week period and that these changes are associated with the type of treatment.
    The Spine Journal. 01/2014;
  • P. Aagaard
    Journal of Science and Medicine in Sport 12/2013; 16:e3. · 2.90 Impact Factor
  • L B Michalsik, K Madsen, P Aagaard
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    ABSTRACT: The present study evaluated the physical demands imposed on female elite team handball players in relation to playing position. Female elite team handball field players were examined during match-play over a 5-year period using video based computerized locomotion analysis of tournament matches. In addition, physiological measurements during match-play and in separate physical tests were carried out. A total distance of 4 002±551 m (group means±SD) was covered per match with a total effective playing time of 50:42±5:50 min:s, while full-time players covered 4 693±333 m. On average, each player (n=83) performed 663.8±99.7 activity changes per match, and the mean speed was 5.31±0.33 km · h-1. High-intensity running constituted 0.8±0.5% of total effective playing time per match corresponding to 2.5±1.8% of the total distance covered. The amount of high-intensity running was reduced (p<0.05) 21.9% in the second half (44.9±16.8 m) compared to the first (57.5±21.3 m). Maximal oxygen uptake (VO2-max) was 3.49±0.37 l O2 · min-1 corresponding to 49.6±4.8 ml O2 · min-1 · kg-1. Mean relative workload during match-play was 79.4±6.4% of VO2-max. Mean total running distance in the Yo-Yo intermittent recovery test (level 1) was 1 436±222 m, which was greater in wing players (1 516±172 m, p<0.05) than pivots (1 360±118 m) and backcourt players (1 352±148 m). In conclusion, modern female elite team handball is a physically demanding intermittent team sport, where players are exposed to high relative workloads with substantial estimated aerobic energy expenditure interspersed by short periods of dominant anaerobic energy production as reflected by the limited amount of high-intensity running. Indications of fatigue and a resulting decline in physical performance were identified, since the amount of high-intensity running and the relative workload levels decreased in the second half. Positional differences were observed, with wing players covering a greater total distance than backcourt players, performing more high-intensity running and demonstrating a better intermittent recovery capacity (Yo-Yo test outcome) compared to both backcourt players and pivots.
    International Journal of Sports Medicine 11/2013; · 2.27 Impact Factor

Publication Stats

6k Citations
579.18 Total Impact Points

Institutions

  • 2005–2014
    • University of Southern Denmark
      • • Institute of Sports Science and Clinical Biomechanics
      • • Institute of Clinical Research
      Odense, South Denmark, Denmark
  • 2013
    • University of Gothenburg
      • Department of Clinical Neuroscience and Rehabilitation
      Göteborg, Vaestra Goetaland, Sweden
  • 2012–2013
    • Aalborg University Hospital
      Ålborg, North Denmark, Denmark
    • Glostrup Hospital
      København, Capital Region, Denmark
    • Lund University
      Lund, Skåne, Sweden
  • 1998–2013
    • Bispebjerg Hospital, Copenhagen University
      • Institute for Sports Medicine
      Copenhagen, Capital Region, Denmark
  • 1996–2013
    • University of Copenhagen
      • • Department of Neuroscience and Pharmacology
      • • Department of Exercise and Sport Sciences
      København, Capital Region, Denmark
  • 2009–2012
    • National Research Centre for the Working Environment
      København, Capital Region, Denmark
    • English Institute of Sport
      Manchester, England, United Kingdom
  • 2008
    • Aarhus University
      • Department of Sport Science
      Aars, Region North Jutland, Denmark
    • Herlev Hospital
      Herlev, Capital Region, Denmark
  • 2007–2008
    • Institute of Sports Medicine Copenhagen
      København, Capital Region, Denmark
  • 2005–2006
    • University of Copenhagen Herlev Hospital
      Herlev, Capital Region, Denmark
  • 2001
    • University of California, Berkeley
      • Department of Integrative Biology
      Berkeley, MO, United States
  • 2000
    • Manchester Metropolitan University
      • Department of Exercise and Sport Science
      Manchester, ENG, United Kingdom
  • 1995
    • Copenhagen University Hospital
      København, Capital Region, Denmark