Lockdown measures to control disease transmission were implemented at the start of the COVID-19 era, worsening the already existing sedentary lifestyle. Reduced physical activity (PA) and unhealthy ...eating habits have a negative impact on mental health in chronically ill patients, including diabetes patients. Mental illness, on the other hand, encourages a sedentary lifestyle, exacerbating all components of metabolic syndrome. While well-controlled diabetic patients with an HbA1c of less than 7% had a less severe clinical presentation and COVID-19 mortality rates, the favorable effect of PA on immunomodulation and immunoregulation should not be neglected. Given recent data indicating that a sedentary lifestyle is the third independent risk factor for COVID-19 complications and death (after advanced age and organ transplant), including regular PA has never been more vital. Since PA has a major impact on both glycemic control and mental health, implementing structured home-based activity programs could improve glycemic control and psychological well-being, hence positively impacting COVID-19 outcomes.
New Findings
What is the central question of this study?
What are the adaptations of protein synthesis and degradation that occur in skeletal muscle in response to high‐intensity interval training ...(HIIT), and what are the magnitudes of the changes in response to HIIT, compared to moderate‐intensity continuous training (MICT), and the mechanisms underlying these changes?
What is the main finding and its importance?
HIIT is more effective than MICT in altering the expression of muscle RING‐finger protein‐1 and muscle atrophy F‐box, and enhancing the autophagic flux in rat soleus muscle. In addition, HIIT could activate the mechanistic target of rapamycin pathway. These findings suggest that HIIT might be an effective exercise strategy for health promotion in skeletal muscle.
This study aimed to investigate the impact of high‐intensity interval training (HIIT) on the proteins involved in protein synthesis, the ubiquitin–proteasome system (UPS) and autophagy in skeletal muscle of middle‐aged rats. Nine‐month‐old male Wistar rats (n = 56) were randomly divided into three groups: a control (C) group, a moderate‐intensity continuous training (MICT) group and a HIIT group. Rats in the training groups ran on treadmills 5 days per week for 8 weeks. The MICT group ran for 50 min at 60% V̇O2 max , while the HIIT group ran for 3 min at 80% of V̇O2 max six times separated by 3‐min periods at 40% V̇O2 max . Aerobic endurance, number of autophagosomes and expression of proteins involved in protein synthesis and degradation in the soleus muscle were measured at three time points: before training, after 4 weeks and after 8 weeks of training. Compared to the C group, HIIT and MICT increased the expression of phosphorylated mechanistic target of rapamycin (mTOR) after 8 weeks (P < 0.05 and P < 0.01, respectively). HIIT increased the expression of muscle RING‐finger protein‐1 (MuRF‐1) after 4 weeks (P < 0.01), and decreased its expression after 8 weeks (P < 0.01). Both HIIT and MICT decreased the expression of muscle atrophy F‐box (MAFbx) after 4 weeks (P < 0.05). HIIT improved the expression of microtubule‐associated protein 1A/1B‐light chain 3 (LC3)‐II (P < 0.05), and decreased the P62 content (P < 0.01) after 4 weeks. The LC3II/LC3I ratio was increased after 8 weeks (P < 0.01). This study demonstrated that HIIT could activate the mTOR pathway, alter the expression of MuRF‐1 and MAFbx proteins, and enhance autophagic flux in soleus muscle of middle‐aged rats.
Alpine skiing is characterized by specific and dynamic conditions and demands constant processing of visual information and fast decision-making. A fast response time is necessary for protective ...movements which reduce the number and severity of additional head impacts. The apparent detriments to visual performance caused by protective headgear are concerning and should be considered moving forward in recreational alpine skiing. The aim of this study was to examine the effects of wearing the three most common combinations of protective headgear in skiing on the timing of visual stimuli perception and adequate response when simulating on-the-slope situations. The sample consisted of 45 recreational-level skiers (27 M, 18 F; age 30.6 ± 8.19 years) who had finished basic alpine skiing school, had been skiing 6–10 years continuously, and were students of Faculty of Kinesiology, University of Zagreb. They did not report any serious medical conditions regarding vision. The overall testing was conducted in the winter season during January and February of 2022. Reaction time on perceived visual stimuli was observed in a way that a skier was approaching behind a participant’s back from both the left and right side. A 2 × 3 (helmet*condition) mixed-model repeated-measures ANOVA was used to determine differences between helmet users and non-users in each tested condition. When observing the results, it was confirmed that the response time of the participants was the slowest when wearing a ski helmet and goggles combined. Furthermore, one of the most important findings was the determined differences in reaction time between helmet users and non-users, i.e., prior helmet users tended to react faster to the upcoming visual stimuli when wearing combined ski helmet and goggles. In the design and construction of the goggles, it is also necessary to pay attention to reducing the thickness of the frame in order to reduce the distance between the eye and the lens, which consequently reduces interference in the peripheral parts of the field of vision. In future studies, the same testing protocol with all the possible combinations of wearing a ski cap, a helmet, sunglasses, and goggles is necessary to gain a clearer insight into the effect of each item of headgear separately and in various combinations.
Introduction: This study investigated the differences in ACTN3, ACE and ADRB3 variants in top-level soccer players who entered the Croatian National Team and the ones who did not but played for two ...best Croatian teams. Material and Methods: The buccal swabs were collected from 56 soccer players playing for the Croatian National Team (N = 31) and/or for one of the two most prestigious Croatian soccer clubs (N = 25). Each participant’s genotype was determined by analyzing the single-nucleotide polymorphism. The ACTN3 gene (rs1815739) on chromosome 11 and the ACE (rs1799752) gene on chromosome 17 were determined. Results: No significant differences between the players who entered the national team and the ones who did not were found in ACTN3 R577X (p = 0.437) and ADRB3 (p = 0.202) polymorphism distribution, while the differences existed in ACE (p = 0.044). The significant differences were determined in the “Athletic index” between the national-team and non-national-team players (p = 0.023). Regarding the position, the “Athletic index” was significantly higher only in national team midfielders (2.50 ±1.08 points vs. 1.38 ±1.06; p = 0.034). Conclusion: It seems that the soccer players with a favorable genetic combination on the ACTN3 gene and ACE gene might have had a better chance to enter the National Team.
The increasing rate of orthopedic procedures, hip arthroplasty in particular, requires improvement of surgical techniques, as well as of the respective rehabilitation protocols. The aim of the study ...was to assess differences in the quality of life and incidence of limping eight years after total hip arthroplasty performed with a minimally invasive or classic approach. This cross-sectional study included 68 patients, i.e. 32 operated with classic approach and 36 with minimally invasive approach during 2011. The following parameters were observed: anthropometric measurements, history of comorbidity, subjective assessment of limping, and SF-36 questionnaire (Short Form Survey Instrument). SF-36 testing, which consists of 8 domains, showed that 5 domains of the quality of life were statistically significantly better in the minimally invasive group (level of significance p<0.05). These domains were role of limitation due to physical health (p=0.01), energy (p=0.02), social functioning (p=0.02), pain (p=0.02) and general health (p=0.00).The minimally invasive group had a statistically significantly lower incidence of limping (p=0.032). Quality of life after hip replacement could be a decisive factor when choosing the type of orthopedic procedure. The higher number of limping patients in the classic approach group may have contributed to differences in the quality of life. In conclusion, the minimally invasive approach enables higher long-term quality of life and functional recovery. Key words: Arthroplasty, hip replacement; Osteoarthritis; Quality of life; Transgluteal approach
Performance-predictive parameters have been established for rowers representing different quality levels, sexes, weight categories and classifications, but none have been designed for very young ...rowers (age <14). The objective of this study was to predict 1000-m rowing ergometer performance based on 12 anthropometric and six physiological variables in 48 male rowers (age range 12.0-13.9 year; mean+/-S.D. 12.94+/-0.61) and to determine the key parameters that would perhaps provide a scientific basis for talent identification and the selection process in rowing. The subjects completed an incremental maximal treadmill test. Their body height (r=-0.79), body mass (r=-0.60), lean body mass (r=-0.82), leg length (r=-0.72), arm length (r=-0.71), bicristal diameter (r=-0.63), biacromial diameter (r=-0.73), upper arm girth (r=-0.34), forearm girth (r=-0.63), thigh girth (r=-0.29), calf girth (r=-0.54), maximal oxygen uptake (in L/min, r=-0.89; and in mL/kg/min, r=-0.36), maximal ventilation (r=-0.77), and oxygen uptake at ventilatory anaerobic threshold (r=-0.87) correlated with 1000-m time (p<0.05), while percent body fat, percent of maximal oxygen uptake at ventilatory anaerobic threshold and maximal lactate did not. Performance correlated significantly with age (r=-0.46; p<0.01), so it was important to consider this effect in the resulting regression models. Multiple regression procedures indicated that the model comprising anthropometric and physiological variables combined best predicts performance (R(2)=0.85), followed by models that comprised physiological (R(2)=0.80) and anthropometric (R(2)=0.76) variables alone. In conclusion, in rowers aged 12-13 year a higher aerobic capacity (as measured by maximal oxygen uptake in L/min), and a larger body size are beneficial for performance over 1000-m rowing ergometer distance.
Testosterone levels in female athletes are increased due to their physical activity and correlate with their exercise volume. We therefore hypothesized that the reference intervals (RIs) derived from ...the general population are not applicable for female athletes. The aim of this study was to evaluate the applicability of the given RIs for 6 commercially available testosterone immunoassays in a group of female athletes.
Our study included 121 female athletes from various sporting disciplines (water polo, handball, volleyball, football, and basketball). The physical activity score was assessed by the Short Form of the International Physical Activity Questionnaire. Total testosterone was measured in serum samples by the reference LC–MS/MS method and six different immunoassays (Abbott Architect 2nd Generation Testosterone, Beckman Coulter Access Testosterone, Roche Elecsys Testosterone II, Siemens Atellica® IM Testosterone II (TSTII), Siemens IMMULITE 2000 Total Testosterone, and Snibe MAGLUMI™ Testosterone).
There were statistically significant differences in age (P = 0.042), weight (P = 0.001), height (P < 0.001), and BMI (P < 0.001) between athletes across different sports. Their quantitative measurements of physical activity and testosterone concentration did not differ significantly between subgroups of various sports, P = 0.167 and P = 0.181, respectively. All immunoassays had a positive absolute and relative bias, in comparison with the LC–MS/MS. The manufacturer’s RI was not verified for Abbott Architect, Beckman Coulter Access, and Roche Elecsys Testosterone methods, with the highest percentage of athletes above RI for Beckman Coulter (30%).
We demonstrated that the upper reference limit provided was too low for some young female athletes. Clinical laboratories should consider implementation of the new proposed RIs.
The benefit of protective headgear for recreational skiers is an ongoing debate in the snow sports industry, and there are a lot of opposing opinions. Due to the dynamic conditions in which winter ...sports are performed, athletes demand rapid and constant processing of visual information. A sufficient level of anticipation helps athletes to properly position themselves to reduce the forces transferred to the head or even move to avoid a collision. To objectively identify the impact of protective headgear on the visual field when skiing, it is necessary to conduct suitable measurements. The sample consisted of 43 recreational-level skiers (27 M, 16 F; age 31.6 ± 8.23 years). A predefined testing protocol on an ortoreter was used to assess the visual field for three conditions of wearing protective headgear. Differences in perceived visual stimuli between the three conditions were evaluated by repeated measures analysis of variance (ANOVA). Based on the observed results, it can be concluded that the combination of wearing a ski helmet and ski goggles significantly negatively influences visual performance in a way that the visual field is narrowed, for both helmet users and non-users, only when comparing the tested conditions. When comparing helmet users and non-users, there are no differences in the amount of visual impairment; therefore, the habit of wearing a helmet does not influence the ability of perceiving visual stimuli.
(1) Background: Individuals' psychological traits can influence not just success in sport but also the ability to learn new motor skills. We investigated whether sport courage, worry and fear differ ...between alpine ski-naive and basic level skiers and how they affect ski learning. (2): A total of 337 students (249 ski-naive and 88 basic level) participated in research consisting of a four-part questionnaire and structured skiing program. (3) Results: For beginners, lower fear (
-0.30,
0.01) and higher Self-efficiency (
0.28,
0.05) and mastery (
0.20,
0.01) were associated with better performance; reducing fear and increasing self-efficiency and worry increased performance. Experienced skiers were better in determination, mastery, and self-efficiency (all
0.05). In case of lower score in worry (
-0.28,
0.01) and higher in self-efficiency (
0.22,
0.05) performance was better. Males scored higher in sport courage scale-31 (all
0.05). In particular, self-efficiency was associated with better (
0.39,
0.01), and higher fear with poorer performance (
-0.33,
0.01). Moreover, self-efficiency was a predictor of ski success (
0.001). On the other hand, females like ski beginners scored higher in fear (
0.001). In females, determination, mastery and self-efficiency had a positive correlation with skiing (
0.21,
0.05,
0.28,
0.01, and
0.33,
0.01, respectively), while association between Fear and skiing (
-0.46,
0.01) was negative, and fear (
0.001) was inversely related to success. (4): Conclusions: Psychological factors and gender differences need to be considered during learning phases of alpine skiing. There is a positive association between self-efficiency and performance of male ski beginners, and negative association between fear and achieved results in basic alpine ski school in case of female ski beginners.
Intensive physical activity causes functional and metabolic changes in the athlete's organism. The study aimed to verify the common national available reference intervals (RIs) for common ...inflammatory and screening coagulation tests in a population of healthy young female athletes.
One hundred and twenty-one female athletes (age range: 16-34), from various sports disciplines (water polo, handball, volleyball, football, basketball), were included in the study. All participants completed the international physical activity short-form questionnaire. Blood samples were collected between 8-10 am, after an overnight fast, before any physical activity. Reference intervals were determined according to Clinical & Laboratory Standards Institute EP28-A3C Guidelines.
Calculated RIs for white blood cell count (WBC), prothrombin time (PT), and activated partial thromboplastin time (APTT) ratio were in accordance with the common national RIs. Calculated RI for C-reactive protein (CRP) was lower (< 2.9 mg/L) than the proposed cut-off for a healthy population (< 5.0 mg/L). Reference interval for fibrinogen was higher (1.9-4.4 g/L), than the available RIs (1.8-3.5 g/L). D-dimer cut-off value was set at 852 µg/L fibrinogen equivalent units (FEU), higher than the proposed 500 µg/L FEU for venous thromboembolism (VTE) exclusion.
The applicability of the available RIs for WBC count, PT, and APTT-ratio was confirmed. However, RIs for CRP and fibrinogen differed significantly than the available common national RIs for the healthy non-athletes' population. A higher cut-off for D-dimers should be extensively verified before implementation for VTE diagnosis exclusion in a group of healthy young female athletes.
PDF
