Low ventilatory responsiveness to transient hypoxia or breath-holding predicts fast marathon performance in healthy middle-aged and older men.

The aim of this study was to test the utility of haemodynamic and autonomic variables (e.g. peripheral chemoreflex sensitivity [PCheS], blood pressure variability [BPV]) for the prediction of individual performance (marathon time and VO2max) in older men. The post-competition vasodilation and sympathetic vasomotor tone predict the marathon performance in younger men, but their prognostic relevance in older men remains unknown. The peripheral chemoreflex restrains exercise-induced vasodilation via sympathetically-mediated mechanism, what makes it a plausible candidate for the individual performance marker. 23 men aged ≥ 50 year competing in the Wroclaw Marathon underwent an evaluation of: resting haemodynamic parameters, PCheS with two methods: transient hypoxia and breath-holding test (BHT), cardiac barosensitivity, heart rate variability (HRV) and BPV, plasma renin and aldosterone, VO2max in a cardiopulmonary exercise test (CPET). All tests were conducted twice: before and after the race, except for transient hypoxia and CPET which were performed once, before the race. Fast marathon performance and high VO2max were correlated with: low ventilatory responsiveness to hypoxia (r = - 0.53, r = 0.67, respectively) and pre-race BHT (r = - 0.47, r = 0.51, respectively), (1) greater SD of beat-to-beat SBP (all p < 0.05). Fast performance was related with an enhanced pre-race vascular response to BHT (r = - 0.59, p = 0.005). The variables found by other studies to predict the marathon performance in younger men: post-competition vasodilation, sympathetic vasomotor tone (LF-BPV) and HRV were not associated with the individual performance in our population. The results suggest that PCheS (ventilatory response) predicts individual performance (marathon time and VO2max) in men aged ≥ 50 yeat. Although cause-effect relationship including the role of peripheral chemoreceptors in restraining the post-competition vasodilation via the sympathetic vasoconstrictor outflow may be hypothesized to underline these findings, the lack of correlation between individual performance and both, the post-competition vasodilation and the sympathetic vasomotor tone argues against such explanation. Vascular responsiveness to breath-holding appears to be of certain value for predicting individual performance in this population, however.

Distribution of Plantar Pressure in Soccer Players.

(1) Background: The aim of this study was to evaluate differences in the static and dynamic distribution of foot pressure on the ground and to investigate the relationships between body mass index (BMI) and mean variables of plantar pressure between soccer players and their non-athlete peers. (2) Methods: The study involved 18 first-division Polish soccer players and 30 non-athlete physiotherapy students. The research experiment was conducted using the FreeMed platform. Basic descriptive statistics were calculated to summarize the variables. Additionally, in the static and dynamic tests, Spearman's rank correlations between body mass index (BMI) and plantar load were calculated. (3) Results: Statistically significant differences between groups were observed in the loading of the dominant limb. A statistically significant correlation between BMI and loading of both limbs was found in the static test and between BMI and loading of the dominant limb in the dynamic test. (4) Conclusions: The baropodometric mat used in our study helped determine the plantar pressure distribution of soccer players and their non-athlete peers. Correlation analysis revealed that BMI was only associated with the mean plantar pressure of the dominant limb in the control group. Further research on a larger group of athletes is needed to determine how much sporting activity may affect the development to modifications within feet in soccer players.

Asymmetry of Musculature and Hand Grip Strength in Bodybuilders and Martial Artists.

The functional preference for the upper limb influences the occurrence of bilateral differences in other segments of the human body. The aim of the study is to assess the influence of the applied fighting technique and targeted physical effort on the occurrence of asymmetry in body musculature and isometric strength in bodybuilders and competitors of selected martial arts. Academic athletes practicing judo (J), jiu-jitsu (JJ), and bodybuilding (BB) were examined. The control group (C) consisted of students who do not practice any sports. The assessment of the body structure was conducted through segmental bioelectrical impedance analysis. Moreover, the study took into account the measurements of left- and right-hand grip strength. In judo, the uneven physical exertion of the right and left sides of the body further increases both directional and absolute asymmetry. Bilateral asymmetry of musculature in jiu-jitsu competitors and bodybuilders occurs to a lesser extent. The control group was characterized by cross-asymmetry. So as to avoid the risk of injury of sportsmen, it is important to consistently supervise and correct their body structure, which also includes the symmetrical participation of the active muscle mass in particular segments. The symmetrisation process should be individualized since each particular sportsman has their own side-to-side body morphology.

Examining relationships of the anterior pelvic tilt angle with the anterior-posterior curvatures and elongation of the spine.

PURPOSE: A pelvic tilt may lead to body posture disturbances. The aim of the study was to determine relationships between the anterior pelvic tilt angle and the curvature and mobility of lumbar lordosis and thoracic kyphosis. METHODS: The angles of anterior pelvic tilt, lumbar lordosis, thoracic kyphosis and spinal elongation were measured with the use of Posturometr-S device. The posturometric measurements were carried out with the pointing stick of the device moving along spinous processes (from C7 to L5) and marking the selected anthropometric points. RESULTS: In the studied group of boys, the angles in a free-standing position and the thoracic kyphosis angle during elongation were significantly greater than the corresponding lordosis angles. In all measured variables the range of measured angles was characteristically wide. The greatest individual differences were found in the lumbar lordosis angles. All the boys featured a significant increase in body height during linear elongation. The measurements of angles at baseline and during elongations of lumbar lordosis and thoracic kyphosis in a standing position in the entire study group revealed that the anterior pelvic tilt had no significant impact on lumbar lordosis in a free-standing posture and its elongation. In the case of thoracic kyphosis, the correlation was statistically significant, although it was not strong. CONCLUSIONS: The anterior pelvic tilt angle is correlated with the subject's age, body mass, body height and the size of thoracic kyphosis.

Anthropometric and strength profiles of professional handball players in relation to their playing position - multivariate analysis.

PURPOSE: In team sports, the varied levels of physical demand associated with different field positions are reflected in the morphofunctional features of the players. The aim of this work was to recognize how the playing position in the team depends on the anthropometric profiles and the strength level of professional handball players. METHODS: A body mass, stature, lower and upper extremity length, circumferences and skinfolds were measured in the male professional athletes. The body composition was analysed using a bioelectrical impedance method. Additionally, hand grip and back strength were measured. A statistical analysis was carried out using routinely statistic methods and principal component analysis. RESULTS: Pivot players usually have the most athletic figure in terms of size and weight and relatively short legs. The backs are characterized by the android body type and low subcutaneous fat content, and a large mass of body cells. The backs and pivots have the same strength of back and hand grip. Goalkeepers have relatively long upper and lower limbs and high back and hand grip strength. The wingers are usually slender, have medium length limbs, low body fat percentage, significant extracellular mass and the lowest muscle strength. CONCLUSIONS: The results of the multivariate analysis were a notable and valuable addition to the study of morphological and strength differences in a group quite homogeneous like a handball team. The principal component analysis allowed for a reduction of the multidimensional structure to three variables describing body massiveness, strength, and the length and height aspect of the body.

Acute effects of contract-relax proprioceptive neuromuscular facilitation stretching of hip abductors and adductors on dynamic balance.

BACKGROUND: Balance control has been shown to play a fundamental role both in everyday life and many athletic activities. An important component of balance control is the somatosensory information gained from muscle spindles and Golgi tendon organs. The changes in the muscle-tendon unit stiffness could alter the ability to detect and respond promptly to changes of an unstable environment. One of the procedures affecting muscle stiffness is stretching, and contract-relax PNF stretching (CRS) is considered as one of the safest and most effective techniques. So far, there are no studies on the impact of CRS of hip adductor and abductor muscles on body balance. These muscle groups are responsible for maintaining mediolateral balance which is of particular interest, since it is more affected by ageing and disease and since its deterioration has been associated with an increased risk of falling. In light of the above, the aim of the present study was to investigate the effects of a single dose of contract-relax proprioceptive neuromuscular facilitation stretching of hip adductors and abductors on mediolateral dynamic balance. METHODS: The study involved 45 healthy individuals (age 19-23 years) assigned to the intervention group (IG) or the control group (CG). Balance testing was carried out before (Pre) and immediately after CRS in the intervention group or after 5-minute rest in the control group (Post). There were performed three repetitions of the CRS targeting the adductor and abductor muscles of the hip. RESULTS: Statistically significant differences between Pre and Post condition were observed only in the intervention group. The values of all measured variables defining the body's dynamic balance were significantly lower immediately after the applied CRS, which indicates an improved body balance: Global Index (p = 0.0001), total area of sway (p = 0.0001), external area of sway (p = 0.00004), external time (p = 0.0004) and reaction time (p = 0.0003). CONCLUSIONS: A single dose of contract-relax proprioceptive neuromuscular facilitation stretching of the hip adductor and abductor muscles improved mediolateral dynamic balance.

Spinal range of motion and plantar pressure in sport climbers.

PURPOSE: The aim of the study was to investigate the range of motion (ROM) of lumbar and thoracic articulations and static and dynamic plantar pressure in sport climbing athletes. METHODS: The sample included 30 sport climbers with a minimum of 2 years training experience and 30 physical education students who served as an active untrained control. ROM was assessed by a Saunders digital inclinometer and plantar pressure by a baropodometric platform. RESULTS: Mean spinal ROMs were greater in the sport climbers with an exception of extension, rotation, and lateral thoracic flexion, with a high degree of statistical significance obtained in the majority of the analyzed ROMs. The climbers exhibited increased mean forefoot pressure (smaller rearfoot pressure) in both the dominant and nondominant extremities, with significant intergroup differences found in dominant forefoot/rearfoot pressure distribution. CONCLUSIONS: Sport climbers present increased lumbar and thoracic ROM. The characteristics of climbing may also affect transverse arch structure and plantar pressure distribution.

Lifestyle of students from different universities in Wroclaw, Poland.

BACKGROUND: Changes in the economic and political system that took place in Poland in recent decades had a significant impact on lifestyles of different social groups, especially in youngsters as vulnerable and open to all novelty and changes. OBJECTIVE: The aim of this study was to evaluate the healthy or non-healthy behaviours including physical activity, diet, time devoted for sleeping, leisure, stress and the use of drugs by students of four universities in Wroclaw. MATERIAL AND METHODS: The study involved 604 students (305 women and 299 men) from four universities in Wroclaw: University of Wroclaw - 25.0%, Wroclaw University of Technology - 24.5%, University School of Physical Education (AWF) - 25.2% and Wroclaw Medical University - 25.3%. A questionnaire developed for this study was used. The questions were both open and closed, one or multiple answers could be matched. The questions related to: physical activity, nutrition, time devoted for sleeping, leisure, stress and stimulants. RESULTS: On the basis of the results it was found that students mostly reported an average level of physical activity. The highest level of physical activity was presented by students of the University School of Physical Education and the lowest by students of the University of Wroclaw. Just one in ten students consumed meals on a regular basis, including one in five studying in the AWF. Almost half of the respondents (48.7%) spent 5-7 hours sleeping. Every tenth student slept less than five hours. Most respondents preferred passive forms of recreation, only one in three practiced sports in their spare time (usually students of the AWF). Every fourth student declared smoking, and more than 90% consumed alcohol. CONCLUSIONS: Lifestyle of majority of the students surveyed did not follow the recommendations of preventive care. The need for more efficient education of students is obvious, which will lead to the future positive changes in their lifestyle, reducing the risk of lifestyle diseases.