No relationship between the digit ratios (2D:4D) and salivary testosterone change: Study on men under an acute exercise

The digit ratio (2D:4D) is said to be a potential marker of exposure to prenatal sex steroids. Some studies suggest that the 2D:4D is also linked with the testosterone response to challenging situations due to organizational effect of prenatal hormonal milieu on adult endocrine functioning. However, up to date, there were only four studies (conducted on small samples) that examined the 2D:4D and the testosterone response to a challenging situation (i.e. physical exertion or aggressive context). Here, we examined the relationship between the 2D:4D and the testosterone change under an acute exercise among 97 men. We found that the digit ratios (the right 2D:4D, the left 2D:4D, and the right minus left 2D:4D) were neither predictors of pre-exercise testosterone, nor the change in testosterone level after a cycling task. Our results add a contradictory to previous studies evidence in a discussion on the links of the 2D:4D and the testosterone change.

Assessment of the physical fitness of road cyclists in the step and ramp protocols of the incremental test

BACKGROUND

The incremental test in laboratory conditions is a method commonly used to evaluate the maximal oxygen uptake and peak power output, which are the good predictors of cycling performance. But the best-designed protocol remains unknown. Therefore, the aim of this study was to examine the physiological and biochemical responses in the incremental ramp on cycle ergometer and to compare with the commonly used step in young road cyclists.

METHODS

Fifty-seven road cyclists took part in the experiment. The tests included two visits to the laboratory during which the anthropometric measurements, incremental test on a cycle ergometer, and examination of acid-base balance and blood lactate concentration were made. A randomly selected half of the subjects made, as the first one, the STEP (50W·3min-1) Test and the RAMP Test (~0,27W·sec-1) a week later. The remaining cyclists made tests in the reverse order.

RESULTS

The peak power output obtained in the RAMP was significantly higher than obtained in the STEP by 18.13W (P<0.05). The maximal oxygen uptake was higher by 1.5 (mL∙kg-1∙min-1) during the RAMP (P<0.05). The postexercise blood lactate concentration was significantly higher by 0.94 mmol∙L-1(P<0.05) in STEP.

CONCLUSIONS

We recommend the use of RAMP Test with linearly increasing workload to determine peak power output, maximal oxygen uptake and ventilatory threshold to precisely programming and control training of young road cyclists.

Effects of Dominance and Sprint Interval Exercise on Testosterone and Cortisol Levels in Strength-, Endurance-, and Non-Training Men

The aim of the study was to investigate the response of testosterone and cortisol to sprint interval exercises (SIEs) and to determine the role of dominance. The experiment was conducted in a group of 96 men, divided into endurance-training, strength-training, and non-training groups. Participants performed SIEs consisting of 5 × 10-s all-out bouts with a 50-s active recovery. Using the passive drool method, testosterone and cortisol concentrations were measured in saliva samples at rest at 10 min pre and 12 min post exercise. Participants’ heart rate (HR) was measured during the whole exercise. Dominance was assessed by the participants before the study; the rating of perceived exertion (RPE) was measured immediately after each bout. The study showed that those who trained in endurance and strength sports had significantly lower mean HRs after five acute 10-s interval bouts than those in the non-training group (p = 0.006 and p = 0.041, respectively). Dominance has an inverse relation to changes in HR; however, it has no relation to hormone response. No significant differences were observed in testosterone and cortisol changes in the endurance-training, strength-training, and non-training groups after SIE (p > 0.05), which may indicate that the exercise volume was too low.

Influence of a Six-Week Swimming Training with Added Respiratory Dead Space on Respiratory Muscle Strength and Pulmonary Function in Recreational Swimmers

The avoidance of respiratory muscle fatigue and its repercussions may play an important role in swimmers' health and physical performance. Thus, the aim of this study was to investigate whether a six-week moderate-intensity swimming intervention with added respiratory dead space (ARDS) resulted in any differences in respiratory muscle variables and pulmonary function in recreational swimmers. A sample of 22 individuals (recreational swimmers) were divided into an experimental (E) and a control (C) group, observed for maximal oxygen uptake (VO2max). The intervention involved 50 min of front crawl swimming performed at 60% VO2max twice weekly for six weeks. Added respiratory dead space was induced via tube breathing (1000 mL) in group E during each intervention session. Respiratory muscle strength variables and pulmonary and respiratory variables were measured before and after the intervention. The training did not increase the inspiratory or expiratory muscle strength or improve spirometric parameters in any group. Only in group E, maximal tidal volume increased by 6.3% (p = 0.01). The ARDS volume of 1000 mL with the diameter of 2.5 cm applied in moderate-intensity swimming training constituted too weak a stimulus to develop respiratory muscles and lung function measured in the spirometry test.

Predicting Changes in Maximal Oxygen Uptake in Response to Polarized Training (Sprint Interval Training, High-Intensity Interval Training, and Endurance Training) in Mountain Bike Cyclists

ABSTRACT

Hebisz, R, Hebisz, P, Danek, N, Michalik, K, and Zatoń, M. Predicting changes in maximal oxygen uptake in response to polarized training (sprint interval training, high-intensity interval training, and endurance training) in mountain bike cyclists. J Strength Cond Res 36(6): 1726-1730, 2022-The aim of this study was to determine the predictors of change in maximal oxygen uptake (ΔV̇o2max) in response to a polarized training program. Twenty well-trained mountain bike cyclists completed an 8-week intervention of sprint interval training (SIT) (8-16 30-second maximal sprints), high-intensity interval training (4-6 bouts at 85-95% maximal aerobic power), and endurance training (2-3 hours cycling at 70-80% power at the ventilatory threshold). An incremental exercise test was performed to determine preintervention and postintervention maximal oxygen uptake (V̇o2max) and maximal pulmonary ventilation (VEmax) normalized to lean body mass (LBM). The frequency and time domain of heart rate variability (HRV) was also determined during recovery after moderate warm-up in the first and last SIT. Training status was quantified as the total distance cycled in the previous year. V̇o2max, VEmax, and the root mean square of the successive differences of normal-to-normal time interval between heartbeats (RMSSD), which is the time domain of HRV all increased significantly. Multiple significant correlations were observed between ΔV̇o2max and training status and baseline measures of VEmax·LBM-1, RMSSD, and V̇o2max·LBM-1 and a regression equation was developed (r = 0.87, r2 = 0.76; p = 0.0001). The change in V̇o2max in response to polarized training can be predicted with high accuracy based on several measurable variables.

Mechanical suture techniques in gastro-intestinal surgery: partial gastrectomy B I and B II

Out of a total of 140 gastro-intestinal procedures performed with mechanical suture techniques 25 partial gastrectomies (according to Billroth I or II) are discussed. Provided the operating instructions are followed and possible complications are avoided, these mechanical techniques have proved advantageous.

Submaximal Verification Test to Exhaustion Confirms Maximal Oxygen Uptake: Roles of Anaerobic Performance and Respiratory Muscle Strength

Background: The incremental exercise test is commonly used to measure maximal oxygen uptake (VO2max), but an additional verification test is often recommended as the "gold standard" to confirm the true VO2max. Therefore, the aim of this study was to compare the peak oxygen uptake (VO2peak) obtained in the ramp incremental exercise test and that in the verification test performed on different days at submaximal intensity. Additionally, we examined the roles of anaerobic performance and respiratory muscle strength. Methods: Sixteen physically active men participated in the study, with an average age of 22.7 ± 2.4 (years), height of 178.0 ± 7.4 (cm), and weight of 77.4 ± 7.3 (kg). They performed the three following tests on a cycle ergometer: the Wingate Anaerobic Test (WAnT), the ramp incremental exercise test (IETRAMP), and the verification test performed at an intensity of 85% (VER85) maximal power, which was obtained during the IETRAMP. Results: No significant difference was observed in the peak oxygen uptake between the IETRAMP and VER85 (p = 0.51). The coefficient of variation was 3.1% and the Bland-Altman analysis showed a high agreement. We found significant correlations between the total work performed in the IETRAMP, the anaerobic peak power (r = 0.52, p ≤ 0.05), and the total work obtained in the WAnT (r = 0.67, p ≤ 0.01). There were no significant differences in post-exercise changes in the strength of the inspiratory and expiratory muscles after the IETRAMP and the VER85. Conclusions: The submaximal intensity verification test performed on different days provided reliable values that confirmed the real VO2max, which was not limited by respiratory muscle fatigue. This verification test may be suggested for participants with a lower anaerobic mechanical performance.

[The position of gastrointestinal suture technique. Advances through mechanical suture methods (author's transl)]

At the present time various materials and methods of manually suturing the gastrointestinal tract are used in parallel. While these methods satisfy basic standards, there is scarcely any detectable difference in the results. Further development in manual suturing with reference to security from failure and reduction of the expenditure of time is unforeseeable. Adhesive methods cannot achieve any importance in the gastrointestinal tract. Presently only the fully mechanical suture methods described at the end of the sixties show promise of possible future development in the gastrointestinal tract. They are suitable for as much as 80% of plastic gastrointestinal operations, but still need statistical comparison of results.

Stiffness and thickness of the upper trapezius muscle increase after repeated climbing bouts in male climbers

Background

Indoor climbing involves overloading the shoulder girdle, including the rotator cuff and upper trapezius muscles. This on the field study aimed to investigate the effects of repeated climbing bouts on morphological and mechanical measures of the upper trapezius muscle.

Materials and Methods

Fifteen experienced male climbers participated in the study. Rate of perceived exertion (RPE), blood lactate concentration ([La^-]_b), and stiffness and thickness over four points of the upper trapezius were assessed before and after a repeated climbing exercise. The procedure for the climbing exercise consisted of five climbs for a total time of 5-minutes per climb, followed by a 5-minute rest.

Results

The analysis showed an increase from baseline to after the 3rd climb (p ≤ 0.01) for RPE and after the 5th climb for [La^-]_b (p ≤ 0.001). Muscle stiffness and thickness increased at all points (1-2-3-4) after the 5th climb (p ≤ 0.01). We found spatial heterogeneity in muscle stiffness and thickness; muscle stiffness was the highest at Point 4 (p ≤ 0.01), while muscle thickness reached the highest values at points 1-2 (both p ≤ 0.01). Moreover, the analysis between the dominant and non-dominant shoulder showed greater stiffness after the 1^st climb at Point 1 (p = 0.004) and after the 5^th climb at Point 4 (p ≤ 0.001).

Conclusions

For muscle thickness, the analysis showed significant changes in time and location between the dominant and the non-dominant shoulder. Bilateral increases in upper trapezius muscle stiffness and thickness, with simultaneous increases in RPE and blood lactate in response to consecutive climbs eliciting fatigue.

Warm-Up With Added Respiratory Dead Space Volume Mask Improves the Performance of the Cycling Sprint Interval Exercise: Cross-Over Study

Special breathing exercises performed during warm-up lead to hypercapnia and stimulation of mechanisms leading to increased exercise performance, but the effect of a device that increases the respiratory dead space volume (ARDSv) during warm-up has not been studied. The purpose of this study was to investigate the effect of 10 min warm-up with ARDSv on performance, physiological and biochemical responses during sprint interval cycling exercise (SIE). During four laboratory visits at least 72 h apart, they completed: (1) an incremental exercise test (IET) on a cycloergometer, (2) a familiarization session, and cross-over SIE sessions conducted in random order on visits (3) and (4). During one of them, 1200 mL of ARDSv was used for breathing over a 10-min warm-up. SIE consisted of 6 × 10-s all-out bouts with 4-min active recovery. Work capacity, cardiopulmonary parameters, body temperature, respiratory muscle strength, blood acid-base balance, lactate concentration, and rating of perceived exertion (RPE) were analyzed. After warm-up with ARDSv, P ET CO2 was 45.0 ± 3.7 vs. 41.6 ± 2.5 (mm Hg) (p < 0.001). Body temperature was 0.6 (°C) higher after this form of warm-up (p < 0.05), bicarbonate concentration increased by 1.8 (mmol⋅L-1) (p < 0.01). As a result, work performed was 2.9% greater (p < 0.01) compared to the control condition. Respiratory muscle strength did not decreased. Warming up with added respiratory dead space volume mask prior to cycling SIE produces an ergogenic effect by increasing body temperature and buffering capacity.

Cognitive Training with Older Adults Using Smartphone and Web-Based Applications: A Scoping Review

INTRODUCTION

The present scoping review focused on: i) which apps were previously studied; ii) what is the most common frequency for implementing cognitive training; and iii) what cognitive functions the interventions most focus on.

METHODS

PRISMA guidelines were followed, and the search was conducted on Web of Science, PsycInfo, Cochrane, and Pubmed. From 1733 studies found, 34 were included.

RESULTS

it was highlighted the necessity for forthcoming investigations to tackle the methodical restrictions and disparities in the domain.

DISCUSSION

great diversity in intervention protocols was found. Incorporating evaluations of physical fitness in conjunction with cognitive evaluations can offer a more all-encompassing comprehension of the impacts of combined interventions. Furthermore, exploring the efficacy of cognitive training applications requires additional scrutiny, considering individual variances and practical outcomes in real-life settings.

Hypercapnic warm-up and re-warm-up-A novel experimental approach in swimming sprint

The purpose of this study was to determine the effective warm-up protocol using an added respiratory dead space (ARDS) 1200 ml volume mask to determine hypercapnic conditions, on the swimming velocity of the 50 m time trial front crawl. Eight male members of the university swimming team, aged 19-25, performed three different warm-up protocols: 1) standardized warm-up in water (WUCON); 2) hypercapnic warm-up in water (WUARDS); 3) hypercapnic a 20-minute transition phase on land, between warm-up in water and swimming test (RE-WUARDS). The three warm-up protocols were implemented in random order every 7th day. After each protocol, the 50 m time trial front crawl swimming (swimming test) was performed. The fastest time trial swimming of 50 m front crawl was achieved after the hypercapnic transition phase (RE-WUARDS) protocol and was 27.5 ± 1.6 seconds, 1.2% faster than hypercapnic warm-up protocol (p = 0.01). This result was confirmed by a higher swimming average speed of the exercise test after RE-WUARDS compared to WUARDS (p = 0.01). The use of ARDS provoked a state of tolerable hypercapnia (obtaining carbon dioxide concentration in arterialized blood pCO2 > 45 mmHg) achieving a post-warm-up of WUARDS value 49.7 ± 5.9 mmHg (compared to the control condition which was a statistically significant difference p = 0.02) and before time trial RE-WUARDS 45.7 ± 2.1 mmHg (p = 0.01 compared to WUCON). After breathing through the 1200 ml ARDS mask during the 20-minute re-warm-up phase, there was a trend of faster time trial among participants compared to the control condition, and statistically significantly faster times compared to WUARDS, indicating that further study is appropriate to verify the efficacy of the proposed method to improve swimming efficiency.