Effects of 8-Week Online, Supervised High-Intensity Interval Training on the Parameters Related to the Anaerobic Threshold, Body Weight, and Body Composition during Pregnancy: A Randomized Controlled Trial.

We aimed to assess the effects of an 8-week, online high-intensity interval training (HIIT) program on the parameters related to the anaerobic threshold (AT), body weight, and body composition in pregnant women. A total of 69 Caucasian women with an uncomplicated singleton pregnancy (age: 31 ± 4 years; gestational age: 22 ± 5 weeks; mean ± standard deviation) were randomly allocated to either an 8-week HIIT program (HIIT group) or to a comparative 8-week educational program (EDU group). Our most important finding was that even with the 8-week progression of pregnancy and physiological weight gain, the HIIT group maintained the same level of parameters related to AT: volume of oxygen at the AT (VO2/AT), percentage of maximal oxygen uptake at the AT (%VO2max/AT), and heart rate at the AT (HR/AT). In contrast, in the EDU group we observed a substantial deterioration of parameters related to the AT. The HIIT intervention substantially reduced the fat mass percentage (median: 30 to 28%; p < 0.01) and improved the total fat-free mass percentage (median: 70% to 72%; p < 0.01). In the EDU group, the body composition did not change significantly. An online, supervised HIIT program may be used to prevent the pregnancy-related risk of excessive weight gain and reduction in exercise capacity without yielding adverse obstetric or neonatal outcomes.

Effect of physical training on parathyroid hormone and bone turnover marker profile in relation to vitamin D supplementation in soccer players.

The aim of the study was to assess the impact of vitamin D supplementation and regular physical activity on 25-hydroxyvitamin D [25(OH)D], parathyroid hormone (PTH) and bone turnover marker concentrations in healthy male athletes. Twenty-five youth soccer players were divided into groups: non-supplemented (GN) and supplemented (GS) with a vitamin D dose of 20 000 IU twice a week for 8 weeks. The study was conducted during an 8-week preseason period, from mid-January to mid-March. At baseline (T1) and at the end of this period (T2), the serum concentrations of 25(OH)D, (PTH), osteocalcin (OC) and ß-isomerized C-terminal telopeptide of type I collagen (ß-CTx) were measured. At T2, 25(OH)D increased by 70% in GS (p = 0.004) and by 6% in GN (p > 0.05). Significant differences between GS and GN groups were observed throughout the study in the group-by-time interaction and changes of 25(OH)D (p = 0.002; η 2 p = 0.36) and OC (p = 0.008; η 2 p = 0.26). Increased OC (ES = 0.74; moderate) and ß-CTx (ES = 1.31, large) in GN athletes who had an optimal baseline vitamin D level (GO) were observed. In GN, at T2, ß-CTx positively correlated with PTH and OC (p = 0.007 and p = 0.002). In GS, ß-CTx positively correlated with OC at both time points (T1, p = 0.027 and T2, p = 0.037). A negative correlation between 25(OH)D and PTH was observed at T2 (p = 0.018). The obtained results suggest that the 20 000 IU vitamin D3 dose applied twice a week for 8 weeks is effective for vitamin D compensation and sufficient to maintain the correct PTH concentration, as revealed by changes in the bone marker concentrations. In conclusion, the results suggest that the applied vitamin D supplementation dose in athletes leads to intensive bone remodelling and has protective effects on bone under intensive physical effort.

Changes of physical match performance after the COVID-19 lockdown in professional soccer players according to their playing position.

The aim of this study was to evaluate the impact of the pandemic lockdown, which included training cessation and home-based training, on physical performance in professional soccer players from the Polish Ekstraklasa according to their playing position. The research was based on 3137 players' individual match performance observations during the 2019/2020 season divided into before (26 matchdays) and after (11 matchdays) lockdown periods. The data were collected using the computerised multiple-camera optical tracking system TRACAB (ChryronHego VID, New York, NY) with a sampling frequency of 25 Hz. Independently of playing position, a significant (p < 0.001) reduction in season resumption metrics of total distance (-0.9%), jogging (-1.6%), running (-3.4%) and high-speed running (-2.5%), with a contemporaneous increase in walking distance (1.4%), was noted in relation to pre-lockdown performance. A reduction in high-speed running was observed in central defenders (p < 0.05), central midfielders (p < 0.01) and forwards (p < 0.05). No significant decrease in sprinting or maximal running velocity was observed. The COVID-19 lockdown negatively influenced the physical performance in professional soccer players.

Effect of Vitamin D3 Supplementation on Interleukin 6 and C-Reactive Protein Profile in Athletes.

Vitamin D3 has a preventive, anti-inflammatory effect. However, there are still few studies linking the effects of athlete training to vitamin D3 supplementation and the immune response. The study evaluated the impact of vitamin D3 supplementation on interleukin 6 (IL-6) release during physical exercise in relation to C-reactive protein (CRP) levels in healthy male athletes. Twenty-five soccer players were divided into two groups-with (GS) and without (GN) vitamin D3 supplementation in a dose of 20,000 IU twice a week for 8 wk (about 6,000 IU/d). At the baseline (T1) and at the end (T2) of the training cycle serum concentrations of 25-hydroxyvitamin D [25(OH)D], IL-6 and CRP were measured. In the GS group, we observed a significant increase in 25(OH)D concentration (p=0.004), and non-significantly increased levels (p>0.05) of IL-6 and CRP. At the baseline, CRP in the supplemented athletes who had suboptimal vitamin D3 concentration in T1 (GSO) was significantly higher than in those with an optimal baseline vitamin D3 level (GO) (p=0.028). However, in GO in T2, a non-significant trend of negative correlation (p=0.055) between 25(OH)D concentration and IL-6 level was found. In the total study group (TG), a statistically significant (p=0.021) negative correlation in T1 was observed between 25(OH)D and CRP. However, our results do not support the immune-modulatory effect of vitamin D3 supplementation in a dose of 6,000 IU/d in athletes, in relation to IL-6 production and its subsequent stimulatory effect on CRP releasing.

Correlation between the Positive Effect of Vitamin D Supplementation and Physical Performance in Young Male Soccer Players.

The aim of this study was to determine whether supplementation with vitamin D during eight weeks of high-intensity training influences muscle power and aerobic performance in young soccer players. A total of 25 athletes were divided into two groups: the supplemented group (GS; n = 12; vitamin D 20,000 IU, twice a week) and the non-supplemented group (GN; n = 13). A set of measurements, including sprint tests, explosive power test, maximal oxygen uptake (VO2max), and serum 25(OH)D concentration, were obtained before (T1) and after (T2) the intervention. A significant group x time interaction was found in the 25(OH)D serum levels (p = 0.002; ES = 0.36, large). A significant improvement in VO2max was found in the TG (p = 0.0004) and the GS (p = 0.031). Moreover, a positive correlation between 25(OH)D and VO2max (R = 0.4192, p = 0.0024) was calculated. The explosive power tests revealed insignificant time interactions in the average 10-jump height and average 10-jump power (p = 0.07, ES = 0.13; p = 0.10, ES = 0.11, respectively). A statistically insignificant trend was observed only in the group-by-time interaction for the sprint of 10 m (p = 0.05; ES = 0.15, large). The present study provides evidence that vitamin D supplementation has a positive but trivial impact on the explosive power and locomotor skills of young soccer players, but could significantly affect their aerobic performance.

The Influence of COVID-19 Pandemic Lockdown on the Physical Performance of Professional Soccer Players: An Example of German and Polish Leagues.

The purpose of this study was to investigate whether the in-season pandemic lockdown influenced physical match performance in professional soccer players who participated in the competition of German Bundesliga and Polish Ekstraklasa. The data from 306 games for German Bundesliga and 296 games for Polish Ekstraklasa were divided into before- and after-lockdown periods. The physical performance of German Bundesliga teams after the 63-day COVID-19 lockdown did not differ significantly from that in the first part of the season. In contrast, Polish Ekstraklasa teams, after the 81-day lockdown, displayed significantly shorter total distances (p < 0.001), shorter high-intensity running distances (p = 0.03), and fewer high-intensity actions (p = 0.02). Moreover, when the effective playing time was considered, teams covered significantly less relative total distance (p < 0.001) and relative high-intensity running distance (p = 0.02). The results of the current study suggest that physical performance during the matches of the German Bundesliga was not influenced by the COVID-19 lockdown, contrary to those of the Polish Ekstraklasa. This difference could have been caused by different break lengths and different restrictions implemented in these countries during the pandemic lockdown.

Gender differences in the association between physical activity and obesity in adults with vision and hearing losses.

BACKGROUND: Physical inactivity is strongly associated with obesity, which in turn is a major risk factor for many non-communicable diseases. We examined associations between physical inactivity and obesity in Spanish adults with vision and hearing difficulties and explored differences between men and women. METHODS: Data from the Spanish National Health Survey 2017 were analyzed [n = 23 089 adults (15-103 years, mean age 53.4 ± 18.9 years, 45.9% men)]. Participants self-reported difficulties in seeing and hearing. Physical inactivity (exposure) was evaluated with the International Physical Activity Questionnaire Short Form. Obesity (outcome) was defined as body mass index ≥30 kg m-2 based on self-reported weight and height. The association between physical inactivity and obesity was assessed with multivariable logistic regression in people with difficulties seeing and hearing, adjusting for significant covariates. RESULTS: Multivariable logistic regression analyses showed that the association between physical inactivity and obesity was stronger in those with difficulty hearing (OR 1.778, 95% CI 1.215-2.602) compared with difficulty seeing (OR 1.375, 95% CI 1.076-1.756). Gender-stratified analyses showed significant association between physical inactivity and obesity in men who reported difficulty hearing (OR 2.319, 95% CI 1.441-3.735) and difficulty seeing (OR 1.556, 95% CI 1.079-2.244), but not in women. CONCLUSIONS: A significant association between physical inactivity and obesity was observed in Spanish men with vision and hearing difficulties. Physical activity has an important role in the prevention of obesity in men with seeing and hearing difficulties. Active steps should be taken to encourage physical activity to reduce the risk of obesity in people with sensory impairments.

Vitamin D and Stress Fractures in Sport: Preventive and Therapeutic Measures-A Narrative Review.

There are numerous risk factors for stress fractures that have been identified in literature. Among different risk factors, a prolonged lack of vitamin D (25(OH)D) can lead to stress fractures in athletes since 25(OH)D insufficiency is associated with an increased incidence of a fracture. A 25(OH)D value of <75.8 nmol/L is a risk factor for a stress fracture. 25(OH)D deficiency is, however, only one of several potential risk factors. Well-documented risk factors for a stress fracture include female sex, white ethnicity, older age, taller stature, lower aerobic fitness, prior physical inactivity, greater amounts of current physical training, thinner bones, 25(OH)D deficiency, iron deficiency, menstrual disturbances, and inadequate intake of 25(OH)D and/or calcium. Stress fractures are not uncommon in athletes and affect around 20% of all competitors. Most athletes with a stress fracture are under 25 years of age. Stress fractures can affect every sporty person, from weekend athletes to top athletes. Stress fractures are common in certain sports disciplines such as basketball, baseball, athletics, rowing, soccer, aerobics, and classical ballet. The lower extremity is increasingly affected for stress fractures with the locations of the tibia, metatarsalia and pelvis. Regarding prevention and therapy, 25(OH)D seems to play an important role. Athletes should have an evaluation of 25(OH)D -dependent calcium homeostasis based on laboratory tests of 25-OH-D3, calcium, creatinine, and parathyroid hormone. In case of a deficiency of 25(OH)D, normal blood levels of ≥30 ng/mL may be restored by optimizing the athlete's lifestyle and, if appropriate, an oral substitution of 25(OH)D. Very recent studies suggested that the prevalence of stress fractures decreased when athletes are supplemented daily with 800 IU 25(OH)D and 2000 mg calcium. Recommendations of daily 25(OH)D intake may go up to 2000 IU of 25(OH)D per day.

[Vitamin D Deficiency in Sports]. / Vitamin-D-Mangel im Sport.

Vitamin D Deficiency in Sports Abstract. A deficiency in vitamin D is very common in the general population as well as in athletes. The aim of this overview is to assess the level of knowledge about the importance of vitamin D for athletes. A deficiency in vitamin D is present in up to 90 % of athletes. Risk groups are young athletes, female athletes, athletes with a limitation such as paraplegia, vegetarians, athletes with a resorption disorder such as celiac disease, athletes training and competing indoors (e.g. ice hockey, basketball, boxing, rhythmic gymnastics), and older athletes. Dark skin pigmentation, the use of sunscreen, the time of day of the training (early morning, late evening) and the geographical location influence the risk for a deficiency in vitamin D. Exposure to the sun and a balanced diet are often not enough to prevent a vitamin D deficiency.

Assessment of the diet of male adolescents suffering from type 1 diabetes.

INTRODUCTION: Currently, 5-10% of diabetes patients are teenagers. During this period the influence of peers and observation of their eating habits plays a significant role. Unfortunately, they differ from the principles of proper nutrition, which according to the PTD Diabetes Poland should be introduced as an element of proper metabolic compensation. Aim of the study: To assess the condition and dietary habits of male adolescents with type 1 diabetes and to compare their eating habits to generally accepted standards. MATERIAL AND METHODS: The study participants include 20 boys, aged 14.6 ±1.58 years, with type 1 diabetes mellitus treated with a personal insulin pump who were diagnosed using ISPAD criteria. In the study anthropometric and questionnaire methods were used, as well as body composition analysis. RESULTS: In most of the examined subjects, the assessment of nutritional status indicates a proper proportion of adipose tissue (14.72 ±6.25%, 8.71 ±4.10 kg per kg) and muscle mass in the body (28.2 ±6.93 kg). Unfortunately in a significant group of adolescents, the diet is not properly balanced. Particularly the common problem is the excess of total carbohydrates, including simple sugars. CONCLUSIONS: To sum up, despite systematic education of proper nutrition on glycemic control and prevention of acute and chronic complications, the eating habits of male adolescents differ from those of proper nutrition. Additionally, it should be noted that despite the proper results of the body composition analysis, there is a problem with an erroneously balanced diet.

Responses to Low- and High-Intensity Exercise in Adolescents with Type 1 Diabetes in Relation to Their Level of VO2 Max.

The purpose of this study was to investigate the influence of maximal oxygen uptake (VO2 max) on the glycemic changes during low and high intensity exercises in young type 1 diabetic patients. Twenty boys (age: 14.3 ± 1.6 years; height: 171.0 ± 11.3 cm; weight; 59.5 ± 12.8 kg) were divided into low-fit group (LFG, n = 10) and high-fit group (HFG, n = 10). According to the experimental design, participants performed three physical efforts (VO2 max test, mixed aerobic-anaerobic effort and aerobic effort) on the cycloergometer, during which real-time glycemia was measured. Mixed aerobic-anaerobic exercise demanded significantly smaller carbohydrate supplementation (0.2 ± 0.2 g/kg during exercise) than the aerobic test session (0.4 ± 0.3 g/kg during exercise). Moreover, patients with higher VO2 max had lower tendency for glycemic changes during the aerobic effort. The results of the current study suggest that young type 1 diabetic patients should perform different intensity activities using continuous glycemic monitoring system to avoid acute and chronic complications of the disease.

Comparison of physical activity levels in Spanish adults with chronic conditions before and during COVID-19 quarantine.

BACKGROUND: This is the first study analyzing levels of physical activity in a sample of quarantined adults with chronic conditions. The aim of this study was to compare moderate- and vigorous-intensity physical activity levels in Spanish adults with chronic conditions before and during coronavirus disease 2019 (COVID-19) quarantine. METHODS: A cross-sectional online survey was administered during the COVID-19 quarantine in Spain. A total of 163 participants with chronic conditions (113 females and 47 males; age range 18-64 years) completed the survey. A total of 26 chronic conditions were included. Participants self-reported average minutes/day of moderate and vigorous physical activity before and during quarantine. Differences in moderate- and vigorous-intensity physical activity levels before and during COVID-19 quarantine (overall, by gender, by age, by number of chronic conditions and by each chronic condition) were assessed by Wilcoxon-signed rank test. RESULTS: During COVID-19 quarantine, there was a significant decrease of moderate-intensity physical activity in Spanish people with chronic conditions (in both males and females, in those aged 18-24, 25-34, 35-44 and 55-64 years, in those with multimorbidity, in those with one/two chronic condition/s, and in those diagnosed with asthma/hypercholesterolaemia/chronic skin disease/haemorrhoids). Also, there was a significant decrease of vigorous-intensity physical activity in Spanish males with chronic conditions and in those with multimorbidity. CONCLUSIONS: These results should be considered to develop effective strategies of physical activity promotion targeting these specific groups when new quarantine or restriction measures are implemented, in order to avoid new significant decreases of physical activity in these vulnerable populations.

Relationships between Training Loads and Selected Blood Parameters in Professional Soccer Players during a 12-Day Sports Camp.

The main purpose of this study is to assess the relations between training loads and selected blood parameters in professional soccer players during a preseason sports camp. Fifteen professional soccer players (age: 24.3 ± 5.25 year; height: 182.6 ± 6.75 cm; weight: 76.4 ± 6.72 kg) participated in the 12-day training camp. All the training sessions and friendly games were accurately analyzed with a GPS system. Blood samples were taken from the players and analyzed before the camp (PRE), in the middle (MID), and one day after the camp (POST). Mean total distance covered by the players during the camp was 85,205 ± 2685 m, high-intensity running 12,454 ± 1873 m, and sprinting 639 ± 219 m. The highest aspartate transaminase (AST), lactate dehydrogenase (LDH), creatine kinase (CK), and C-reactive protein (CRP) values were observed after six days of the camp. The application of intensive training during a 12-day sports camp can be associated with chronic muscle pain with high activity of some blood enzymes (CK, AST) and a high concentration of myoglobin (Mb). During training camps longer than 10 days, it would be necessary to apply, every second or third day, one day of rest, and the training load should not exceed two units every day.

Comparison of physical activity levels in Spanish people with diabetes with and without cataracts.

BACKGROUND: The objective was to compare levels of physical activity (PA) in a large sample of Spanish people with diabetes with and without cataracts. To our knowledge, this is the first study comparing PA levels in people with diabetes with and without cataracts in a large representative sample. METHODS: Cross-sectional data from the Spanish National Health Survey 2017 were analyzed (n = 1014 people with diabetes; 43.1% females; age range 15-69 years; mean age 58.4 ± 9.2 years). International Physical Activity Questionnaire (IPAQ) short form was used to measure PA. Total MET-min week-1 of PA were calculated and participants were divided into two categories according to American Diabetes Association PA guidelines: (i) <600 MET-min week-1. (ii) At least 600 MET-min week-1. Diabetes and cataracts were self-reported in response to the questions 'Have you ever been diagnosed with diabetes/cataracts?' Participants also reported other variables including age, gender, marital status, living as a couple, education, smoking, alcohol consumption and obesity. Statistical analysis was performed with SPSS 23.0. RESULTS: The overall prevalence of cataract was 14.0% and the overall prevalence of people doing <600 MET-min week-1 of PA was 35.4%. The prevalence of cataract was significantly lower in those doing more PA (12.1% vs. 17.5%; P = 0.016). Those without cataracts were significantly more active than those with cataracts (1846.8 vs. 1289.4 MET-min week-1; P = 0.001). The adherence to American Diabetes Association PA guidelines was significantly higher in those without cataracts (66.1% vs. 55.6%; P = 0.016). CONCLUSIONS: Interventions to promote PA targeting people with both diabetes and cataracts are warranted.

The Effect of Vitamin D3 Supplementation on Hepcidin, Iron, and IL-6 Responses after a 100 km Ultra-Marathon.

Deficiencies in iron and vitamin D are frequently observed in athletes. Therefore, we examined whether different baseline vitamin D3 levels have any impact on post-exercise serum hepcidin, IL-6 and iron responses in ultra-marathon runners. In this randomized control trial, the subjects (20 male, amateur runners, mean age 40.75 ± 7.15 years) were divided into two groups: experimental (VD) and control (CON). The VD group received vitamin D3 (10,000 UI/day) and the CON group received a placebo for two weeks before the run. Venous blood samples were collected on three occasions-before the run, after the 100 km ultra-marathon and 12 h after the run-to measure iron metabolism indicators, hepcidin, and IL-6 concentration. After two weeks of supplementation, the intervention group demonstrated a higher level of serum 25(OH)D than the CON group (27.82 ± 5.8 ng/mL vs. 20.41 ± 4.67 ng/mL; p < 0.05). There were no differences between the groups before and after the run in the circulating hepcidin and IL-6 levels. The decrease in iron concentration immediately after the 100-km ultra-marathon was smaller in the VD group than CON (p < 0.05). These data show that various vitamin D3 status can affect the post-exercise metabolism of serum iron.

Acute Responses to Low and High Intensity Exercise in Type 1 Diabetic Adolescents in Relation to Their Level of Serum 25(OH)D.

The main purpose of this study was to investigate the differences in glycaemic reaction in response to various physical activities in 20 young boys (14.4 ± 1.6 years) with type 1 diabetes mellitus (T1DM) and with either vitamin D deficiency or with suboptimal levels of vitamin D. Participants were divided into two groups (deficiency group-DG, n = 10; suboptimal group-SG, n = 10) according to their vitamin D levels. All patients performed aerobic and mixed (aerobic-anaerobic) physical efforts. During the exercise, the respiratory responses and glucose levels were monitored. Biochemical blood analyses were performed before each physical effort. The oxygen consumption was not significantly lower in SG during both aerobic and mixed effort (4.0% and 5.6%, respectively). The glycated haemoglobin (HbA1c) level was higher by 6.1% and the total daily dose of insulin (DDI) was higher by 18.4% in the DG. The differences were not statistically significant. Patients with lower vitamin D levels demonstrated an insignificantly higher glycaemic variability during days with both aerobic and mixed exercises. An appropriate vitamin D concentration in T1DM patients' blood may constitute a prophylactic factor for hyperglycaemia during anaerobic training and hypoglycaemia during aerobic training.

The Association Between Physical Activity and Cataracts Among 17,777 People Aged 15-69 Years Residing in Spain.

PURPOSE: The aim of the present study was to assess the association between levels of physical activity (PA) and the presence of cataracts in people aged 15-69 years residing in Spain. METHODS: Cross-sectional data from the Spanish National Health Survey 2017 were analysed (n = 17,777 ≥ 15 years; 52% females; self-weighting sample). The International Physical Activity Questionnaire (IPAQ) short form was used to measure PA. Total PA MET-minutes/week were calculated, and participants were divided into two categories: 1) Less than 600 MET-minutes/week. 2) At least 600 MET-minutes/week, equivalent to meeting current PA recommendations. Cataracts were self-reported in response to the question "Have you ever been diagnosed with cataracts?". Multivariable logistic regression was used to assess associations overall and by age groups (15-49, 50-64, and 65-69 years; 15-49 and 50-69 years). Covariates included in the analysis were sex, education, BMI (Body Mass Index), multimorbidity, smoking, and alcohol consumption. RESULTS: The overall prevalence of cataract was 3.7%, and the overall prevalence of participating in less than 600 MET-minutes/week of PA was 30.2%. In the adjusted overall analysis, less than 600 MET-minutes/week of PA was associated with significantly higher odds for cataract: OR = 1.324 (95% CI = 1.116-1.571). Age-stratified analyses showed that the association between PA and cataract was significant only in the age groups of 65-69 years and 50-69 years. CONCLUSIONS: A significant association between PA and cataract was observed in people aged 15-69 years residing in Spain. Considering the impact on health and quality of life due to reduced PA in people with cataract, at least 600 MET-minutes/week activity should be promoted.

Prenatal high-low impact exercise program supported by pelvic floor muscle education and training decreases the life impact of postnatal urinary incontinence: A quasiexperimental trial.

BACKGROUND: Pregnancy and high impact exercise may cause postnatal urinary incontinence. We aimed to evaluate the life impact of postnatal urinary incontinence in women attending prenatal, high-low impact exercise program, supported by pelvic floor muscle education and training, in comparison to controls. METHODS: It was a quasiexperimental trial among 260 postpartum Caucasian women (age 29 ±â€Š4 years; mean ±â€Šstandard deviation). The training group (n = 133) attended a high-low impact exercise and educational program from the 2nd trimester of pregnancy until birth, 3 times a week. We educated this group to contract and relax pelvic floor muscles with surface electromyography biofeedback and instructed how to exercise postpartum. Control women (n = 127) did not get any intervention. All women reported on the life impact of urinary incontinence 2 months and 1 year postpartum using the Incontinence Impact Questionnaire (IIQ). RESULTS: Training group started regular pelvic floor muscle exercises substantially earlier postpartum than controls (P < .001). Significantly less training women reported the life impact of urinary incontinence both 2 months (P = .03) and 1 year postpartum (P = .005). Two months after birth, for the symptomatic women the IIQ scores were significantly lower in the training than in the control women (median [Me] = 9.4 vs Me = 18.9; P = .002). Between the 1st and 2nd assessments the number of women affected by incontinence symptoms decreased by 38% in the training group and by 20% in the controls. CONCLUSION: High-low impact activities supported by pelvic floor muscle exercises and education should be promoted among pregnant, physically active women. Such activities may help women to continue high-intensity exercise with the simultaneous prevention of postnatal urinary incontinence.Thy study was registered at ISRCTN under the title "Pelvic floor muscle training with surface electromyography" (DOI 10.1186/ISRCTN92265528).

Correlations between body composition, aerobic capacity, speed and distance covered among professional soccer players during official matches.

BACKGROUND: The importance of sprinting and high-speed running activities during a soccer match is indisputable. The main purpose of this study was to investigate the relations between the players' speed, aerobic capacity, body composition and distance covered in different speed zones during official soccer matches and to compare the match performance variables according to playing position. METHODS: Twenty-three professional soccer players (age: 27.9±4.58 y, body mass: 78.8±7.35 kg, height: 181.7±6.53 cm) participated in this study. During 13 weeks of the competitive season, players participated in 16 official matches and completed body composition analyses, sprint tests, multistage shuttle run tests (MST), and incremental running tests (IRTs). RESULTS: Significant negative correlations were found between sprint distance and percent of fat mass (FM; r=-0.57, P<0.0001), MST (r=0.45, P<0.001), maximal speed (r=0.44, P<0.001). High-speed running (HSR) distance covered by the players during the matches was significantly correlated with FM (r=-0.38, P<0.001) and MST distance (r=0.30, P<0.01). CONCLUSIONS: These data indicate that professional soccer players with lower fat content and higher levels of aerobic capacity are able to cover longer distances in sprinting and HSR during official matches.

Relationships between the Expression of the ACTN3 Gene and Explosive Power of Soccer Players.

Muscle strength and maximal speed are factors determining athlete's results during competition. Their association with ACTN3 gene activity has been documented. The purpose of this study was the analysis of ACTN3 gene expression during a 2 month training cycle of soccer players and its correlation with the countermovement jump (CMJ) and squat jump (SJ). The study group consisted of 22 soccer players (aged 17-18). The study material included peripheral blood lymphocytes. The relative expression (RQ) of the ACTN3 gene was analyzed by qPCR and performed before and after the two-month training cycle. Before the training cycle low expression levels of ACTN3 (median RQ = 0.95) were observed, yet after the training cycle they were elevated (median RQ = 1.98) ( p = 0.003). There was an increase in performance of both jumps: SJ (p = 0.020) and CMJ (p = 0.012) at the end of the training cycle. A simultaneous increase in the ACTN3 gene expression level and height in both jump tests was observed in 73% of athletes (p > 0.05). There were no significant relationships between the ACTN3 gene expression level and the results of the CMJ and SJ. However, explosive strength is a complex feature shaped by many different factors and it could be the reason why we did not observe correlations between these variables.