BACKGROUND: To prevent the risk of stair descent falls and associated injuries in the older adults, it is important to understand the factors that affect this frequent locomotion of daily living. The fact that falls are in most cases the result of the interaction between intrinsic and extrinsic factors is very often underestimated when designing test protocols. RESEARCH QUESTION: This study aimed at evaluating balance control during and immediately after step down onto an unstable surface. METHODS: Physically active men and women aged 60-69 years (n = 28) and 70-79 years (n = 18) were asked to perform a step down onto a foam pad and stand still for 30 s (restabilization phase). Centre of pressure (CoP) velocity and standard deviation of CoP sway in anteroposterior and mediolateral direction were evaluated during the step down (CoP VAP, CoP VML, CoP SDAP, CoP SDML) and in the first 5 s of restabilization (CoP VAP5, CoP VML5, CoP SDAP5, CoP SDML5). In addition, time to complete step was investigated. RESULTS: Participants aged 70-79 years presented worse ML balance control after step down onto an unstable surface than their younger counterparts. This was represented by the significantly higher values of CoP SDML5 and CoP VML5 (p = 0.022 and p = 0.017). No other significant differences were detected. SIGNIFICANCE: Age is associated with a more significant ML center of pressure velocity and sway after step down onto a foam pad in physically active older adults. Exercises aimed at improving ML balance control in unstable conditions should be the subject of physical interventions even in older adults with overall good state of health and physical fitness.

• MeSH
• cvičení * MeSH
• fyzikální vyšetření MeSH
• lidé MeSH
• lokomoce MeSH
• posturální rovnováha * MeSH
• senioři MeSH
• terapie cvičením MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The purpose was to investigate whether runners who do not squat their body weight once will not be overloaded with a weight vest with a load of 5% of BW and will not maintain 95% intensity across ten repetitions of a 20-meter sprint. Eight adult female students (24,05±1,15 years old; body height 168±4,24 cm; body weight 60,39±5,53 kg) from the faculty of sports studies at Masaryk University in the Czech Republic participated in this study. Categories were: 1 = NBW (1RM in the squat is relative body weight ± 5 kg), 2 = LBW (1RM in the squat is lower than BW-5 kg) and 3 = HBW (1RM in the squat is higher than BW +5 kg). The measurements took place on three different days, each day running with another experimental condition: free sprinting, weighted vest sprinting with a 5% load of BW, and weighted vest sprinting with a 5% load of 1RM squat. With a weight vest with resistance at the level of 5% of body weight, during 49 sprints, the intensity decreased by a maximum of 4.82% (participant 4, NBW group, 1st run). Although, with weight vest resistance at the level of 5% of the 1RM back squats, during 68 sprints, the intensity decreased by a maximum of 6.59% (participant 1, NBW group, 8th run). It seems that the level of strength abilities of the lower limbs did not play a role in this, we can calculate 5% intensity from both BW and 1 RM squat. Since the HBW group could maintain the required intensity even at significantly higher weights than 5% BW, further research with a larger research sample is needed.

High-intensity intermittent performance in soccer is widely assessed using the yo-yo intermittent recovery level 2 test (YYIR2). This test is usually associated with aerobic-anaerobic performance. However, less is known about the direct or indirect contributions of abilities, including the anaerobic component. This study aims to propose a three-level model of factors contributing to YYIR2 performance, based on the investigation of relationships with aerobic endurance, repeated-sprint ability (RSA), and the linear and change-of-direction speed and power variables. Eighteen soccer players performed the YYIR2, with a 20-m shuttle run test (20mSR), an RSA test with change-of-direction, 5-m and 20-m sprints, and a 505 test, countermovement jump, squat jump, and drop jump. The results showed a significant relationship between the YYIR2 distance and the 20mSR distance (r = 0.721, p = 0.001), as well as with the RSA test mean time (r = -0.594, p = 0.009). In the second level, the 20mSR distance performance was not associated with any of the speed and power variables. However, the RSA test mean time correlated with the 5-m sprint (r = 0.587, p = 0.010), 20-m sprint (r = 0.702, p = 0.001), and 505 test (r = 0.585 p = 0.011) performance. In the third level, the 20-m sprint time was related to the squat jump (r = -0.577 p = 0.012) and countermovement jump (r = -0.768 p < 0.001) heights. In addition to aerobic endurance, this study highlights the importance of the anaerobic component in YYIR2 performance. More specifically, aerobic endurance (52%) and RSA (36%) are the main determinants of YYIR2 performance. Subsequently, the RSA performance is determined by the linear (34-49%) and change-of-direction speed (35%), while the explosive power of lower limbs contributes to sprinting performance (33-59%). Coaches should focus on the development of these abilities to improve the high-intensity intermittent performance of soccer players.

• MeSH
• běh * MeSH
• fotbal * MeSH
• lidé MeSH
• postura těla MeSH
• sportovní výkon * MeSH
• zátěžový test metody   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

• MeSH
• lidé MeSH
• motivace MeSH
• posturální rovnováha * MeSH
• senioři MeSH
• sporty MeSH
• svalová síla MeSH
• terapie cvičením * metody   MeSH
• úrazy pádem prevence a kontrola   MeSH
• Check Tag
• lidé MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• kazuistiky MeSH
• práce podpořená grantem MeSH

BACKGROUND: Ankle Kinesio-taping (KT) is being globally used an intervention to provide the ankle joint complex with sufficient support against sudden excessive mechanical stress during various activities. However, its effects on proximal joints are unclear. This study investigated the impact of ankle KT on ankle-knee joint coupling in sagittal, frontal and transverse planes. METHODS: Adopting a pretest post-test study design, 30 collegiate athletes with chronic ankle instability performed 3 single-leg drop landings in each non-taped and Kinesio-taped conditions and their movement kinematics were recorded using 6 optoelectronic cameras. RESULTS: The ankle angular velocities in sagittal (P=0.038, d=0.64) and transverse planes (P=0.001, d=0.95) decreased after KT application, while the knee internal rotation velocities increased (P=0.020, d=0.51). The coupling angles revealed that the ankle movement ratios significantly decreased in 3 planes in comparison with knee movement ratios. CONCLUSIONS: Outcomes of this study illustrated that application of ankle KT leaves the individuals with a stiffer ankle joint, which increases the mechanical stresses to this joint and decreases its stiffness in absorbing the applied shocks. Further, ankle KT application resulted in more knee internal rotation moments and may increase the risk of knee injuries during landing after a long-term usage in patients with instability ankle sprain.

• MeSH
• biomechanika MeSH
• dospělí MeSH
• hlezenní kloub fyziologie   MeSH
• kolenní kloub fyziologie   MeSH
• lidé MeSH
• nestabilita kloubu prevence a kontrola   MeSH
• poranění kolena etiologie   MeSH
• poranění kotníku prevence a kontrola   MeSH
• rotace škodlivé účinky   MeSH
• tejpovací páska škodlivé účinky   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Purpose: Simulated competition as a training tool has a relevant role in enhancement of exercise intensity, motivation and physical enjoyment. Including a competitive component into the agility training could represent another way to improve agility performance significantly more. The aim of this study was to assess the effect of agility training performed in the form of competitive exercising on agility performance. Methods: Twenty-two athletes were randomly assigned to an experimental or a control group. Both groups completed the same eight-week agility training, but only the experimental group performed exercises in the form of head-to-head competition. Prior to and after the training, agility time in the Agility Dual test (performed in pairs in the form of head-to-head competition) and Agility Single test (performed individually) was measured. In addition, simple and two-choice reaction time and speed of step initiation were also assessed. Results: A significant group × time interaction effect was observed for agility time in the Agility Dual test only (p = .002). This effect occurred in favor of experimental group (18%, p < .01). No further significant interactions were detected. Conclusions: Competitive agility training led to significant improvement of agility time under competitive conditions only. This training does not contribute to more pronounced improvements of other reaction and speed abilities.

• MeSH
• cvičení fyziologie   MeSH
• dospělí MeSH
• kompetitivní chování fyziologie   MeSH
• lidé MeSH
• mladý dospělý MeSH
• sportovní výkon fyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• randomizované kontrolované studie MeSH

Stair descent is one of the most common forms of daily locomotion and concurrently one of the most challenging and hazardous daily activities performed by older adults. Thus, sufficient attention should be devoted to this locomotion and to the factors that affect it. This study investigates gender and age-related differences in balance control during and after stair descent on a foam mat. Forty-seven older adults (70% women) and 38 young adults (58% women) performed a descent from one step onto a foam mat. Anteroposterior (AP) and mediolateral (ML) centre of pressure velocity (CoP) and standard deviation of the CoP sway were investigated during stair descent and restabilization. A two-way analysis of variance (ANOVA) revealed the main effects of age for the first 5 s of restabilization. Older women exhibited significantly higher values of CoP sway and velocity in both directions compared to the younger individuals (CoP SDAP5, 55%; CoP SDML5, 30%; CoP VAP5, 106%; CoP VML5, 75%). Men achieved significantly higher values of CoP sway and velocity only in the AP direction compared to their younger counterparts (CoP SDAP5, 50% and CoP VAP5, 79%). These findings suggest that with advancing age, men are at higher risk of forward falls, whereas women are at higher risk of forward and sideways falls.

• MeSH
• chůze (způsob) fyziologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• lokomoce fyziologie   MeSH
• mladý dospělý MeSH
• posturální rovnováha fyziologie   MeSH
• senioři MeSH
• sexuální faktory MeSH
• úrazy pádem * MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Balance and lower limb strength deficits are associated with a high incidence of falls in older adults. This study investigated the association between balance control during and after stair descent onto a compliant surface and lower limb strength. Thirty-five women and 14 men participated in this study. Stair descent time, mean center of pressure velocity in anteroposterior and mediolateral direction during stair descent (CoP VAP and CoP VML), and CoP velocity in the first 5 s of restabilization phase (CoP V5) were evaluated. Bilateral strength of the knee flexors and extensors, and ankle plantar and dorsal flexors was evaluated. Spearman correlation analysis with Bonferroni correction yielded a significant association between the strength of the knee flexors on the trailing limb and stair descent time in women (r = 0.502, p = 0.002, R2 = 0.246). The same analysis in men revealed a significant association between the strength of the knee flexors on the trailing limb and CoP VAP (r = -0.820, p < 0.001, R2 = 0.280) and CoP VML (r = -0.697, p = 0.006, R2 = 0.359). The strength of the ankle plantar flexors on the trailing limb was significantly associated with stair descent time (r = 0.684, p = 0.007, R2 = 0.429) and CoP VAP (r = -0.723, p = 0.003, R2 = 0.408) in men. Stair descent balance control is associated with knee flexion strength on trailing limb in women, and with ankle plantar flexion and knee flexion strength on the same limb in men.

• MeSH
• biomechanika MeSH
• hlezenní kloub * MeSH
• kolenní kloub MeSH
• koleno MeSH
• kosterní svaly MeSH
• kotník * MeSH
• lidé MeSH
• senioři MeSH
• svalová síla MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

OBJECTIVES: To determine the effects of ankle Kinesio-taping (KT) on postural sway, lower limb ROM, and muscle activity during a unilateral balance tasks. DESIGN: Case control study design. SETTING: Data were collected at the human movement analysis laboratory. PARTICIPANTS: 30 collegiate athletes with chronic ankle sprain (11 females and 19 males, 23.91 ± 2.58 years). MAIN OUTCOME MEASURE: Hip, knee and ankle joints ranges of motion (ROMs); postural sway area and velocities in both anteroposterior and mediolateral directions; and muscular activity amplitudes (% peak) of lateral and medial gastrocnemius, tibialis anterior and peroneus longus in a 20s single leg balance test in two non-taped (control) and KT (intervention) conditions. RESULTS: Significant decrease observed in ankle lateral ROM (p = 0.048, d = 0.52), mediolateral postural sway velocity (p = 0.029, d = 1.25), and peroneus longus activity amplitudes (p = 0.042, d = 0.55) after KT application. CONCLUSION: Acute application of KT among athletes with chronic ankle instability could provide lateral mechanical support to the ankle, potentially decreasing the velocity of frontal plane sway, and decreasing the magnitude of muscle activation. These data suggest that KT may be beneficial for improving static joint stability among individuals with chronic ankle sprain, and thus could be considered an option to allow safe return-to-activity.

• MeSH
• biomechanika MeSH
• dospělí MeSH
• hlezenní kloub patofyziologie   MeSH
• kosterní svaly patofyziologie   MeSH
• lidé MeSH
• mladý dospělý MeSH
• nestabilita kloubu etiologie   patofyziologie   rehabilitace   MeSH
• pohyb fyziologie   MeSH
• poranění kotníku komplikace   patofyziologie   rehabilitace   MeSH
• posturální rovnováha fyziologie   MeSH
• rozsah kloubních pohybů fyziologie   MeSH
• sportovci * MeSH
• studie případů a kontrol MeSH
• tejpovací páska * MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

The back is subjected to a great deal of strain in many sports. Up to 20% of all sports injuries involve an injury to the lower back or neck. Repetitive or high impact loads (e.g., running, gymnastics, skiing) and weight loading (e.g., weightlifting) affect the lower back. Rotation of the torso (e.g., golf, tennis) causes damage to both, the lumbar and thoracic spine. The cervical spine is most commonly injured in contact sports (e.g., boxing, football). One of the factors that increases the odds of injuries in athletes is excessive and rapid increases in training loads. In spite of currently emerging evidence on this issue, little is known about the balance between physiological loading on the spine and athletic performance, versus overloading and back pain and/or injury in athletes. This scoping review aims (i) to map the literature that addresses the association between the training load and the occurrence of back pain and/or injury, especially between the Acute:Chronic Workload Ratio (ACWR) and back problems in athletes of individual and team sports, and (ii) to identify gaps in existing literature and propose future research on this topic. A literature search of six electronic databases (i.e., MEDLINE, PubMed, Web of Science, SCOPUS, SportDiscus, and CINAHL) was conducted. A total of 48 research articles met the inclusion criteria. Findings identified that fatigue of the trunk muscles induced by excessive loading of the spine is one of the sources of back problems in athletes. In particular, high training volume and repetitive motions are responsible for the high prevalence rates. The most influential are biomechanical and physiological variations underlying the spine, though stress-related psychological factors should also be considered. However, limited evidence exists on the relationship between the ACWR and back pain or non-contact back injuries in athletes from individual and team sports. This may be due to insufficiently specified the acute and chronic time window that varies according to sport-specific schedule of competition and training. More research is therefore warranted to elucidate whether ACWR, among other factors, is able to identify workloads that could increase the risk of back problems in athletes.

• Publikační typ
• časopisecké články MeSH
• přehledy MeSH