Assessment of the Relationship between Periodontitis and Cardiac Parameters in Patients with Early Chronic Heart Failure: A Cross-Sectional Study.

Periodontal disease (PD) is considered a risk factor for cardiovascular events. However, its relationship to chronic heart failure (CHF) is unclear. The aim was to compare cardiac and inflammatory parameters in CHF patients with (PG) versus without periodontitis (NPG). The following parameters were recorded in 58 patients: periodontal screening and recording (PSR), troponin T, NT-proBNP, C-reactive protein (CRP), interleukin-6 (IL-6), blood pressure, heart rate, ejection fraction (EF), ventricular systolic and diastolic function parameters, incremental test, and three questionnaires (Mediterranean Diet Adherence Screener, MEDAS; Oral Health Impact Profile, OHIP-14; Patient Health Questionnaire, PHQ). The serum levels of NT-proBNP and troponin T were significantly higher in the PG, and the left ventricular systolic and diastolic function parameters were significantly lower. The correlation analysis showed age as the only independent risk factor for periodontitis and cardiac biomarkers. No significant group differences were found in the MEDAS, OHIP-14, and PHQ scores, or in CRP, IL-6, and cardiocirculatory parameters. Overall, the BMI correlated significantly with the mean PSR and total cholesterol. The occurrence of increased PSR together with increased age and cardiac risk parameters does not exclude an association between periodontitis and CHF, though no positive correlation was calculated. Periodontitis may be a modifiable risk factor for CHF. Its treatment may help to control the inflammatory burden.

Sports Diet and Oral Health in Athletes: A Comprehensive Review.

Food and fluid supply is fundamental for optimal athletic performance but can also be a risk factor for caries, dental erosion, and periodontal diseases, which in turn can impair athletic performance. Many studies have reported a high prevalence of oral diseases in elite athletes, notably dental caries 20-84%, dental erosion 42-59%, gingivitis 58-77%, and periodontal disease 15-41%, caused by frequent consumption of sugars/carbohydrates, polyunsaturated fats, or deficient protein intake. There are three possible major reasons for poor oral health in athletes which are addressed in this review: oxidative stress, sports diet, and oral hygiene. This update particularly summarizes potential sports nutritional effects on athletes' dental health. Overall, sports diet appropriately applied to deliver benefits for performance associated with oral hygiene requirements is necessary to ensure athletes' health. The overall aim is to help athletes, dentists, and nutritionists understand the tangled connections between sports diet, oral health, and oral healthcare to develop mitigation strategies to reduce the risk of dental diseases due to nutrition.

A new approach to quantify visceral fat via bioelectrical impedance analysis and ultrasound compared to MRI.

BACKGROUND: Visceral adipose tissue (VAT) has been linked to systemic proinflammatory characteristics, and measuring it accurately usually requires sophisticated instruments. This study aimed to estimate VAT applying a simpler method that uses total subcutaneous fat and total body fat (BF) measurements. METHOD: As part of our experimental approach, the subcutaneous fat mass (SFT) was measured via US (SFTtotal), and VAT was quantified by assessing MRI data. Both parameters were added to obtain total body fat (BFcalc). Those results were then compared to values obtained from a bioelectrical impedance analysis (BFBIA). Multiple regression analyses were employed to develop a simplified sex-specific equation for SFT, which was subsequently used in conjunction with BFBIA to determine VAT (VATEq). RESULT: We observed excellent reliability between BFBIA and BFcalc, with no significant difference in body fat values (20.98 ± 8.36 kg vs. 21.08 ± 8.81 kg, p = 0.798, ICC 0.948). VATEq_female/male revealed excellent reliability when compared to VATMRI, and no significant difference appeared (women: 0.03 ± 0.66 kg with a 95% CI ranging from -1.26 kg to 1.32 kg, p = 0.815, ICC: 0.955.; men: -0.01 ± 0.85 kg with a 95% CI ranging from -1.69 kg to 1.66 kg, p = 0.925, ICC: 0.952). CONCLUSION: Taking an experimental approach, VAT can be determined without MRI.

Impact of home-based training and nutritional behavior on body composition and metabolic markers in cancer patients: data from the CRBP-TS study.

Introduction: Obesity and physical inactivity are known to affect cancer's development and prognosis. In this context, physical aerobic and resistance training as well as a Mediterranean nutrition have been proven to have many positive health effects. The aim of this study was therefore to investigate the effect of home-based training on body composition and certain metabolic laboratory parameters. Methods: Patients with breast, colorectal and prostate cancer who underwent curative surgery at stages T1N0M0-T3N3M0 were eligible for this trial and randomized to an intervention and control group. In the intervention group the patients carried out online-based strength-endurance home training during the 6-month study period. Body composition was assessed via bioelectrical impedance analysis (baseline, 3 months and 6 months). Metabolic blood parameters were also analyzed and nutrition behavior determined using the Mediterranean Diet Adherence Screener (MEDAS). Results: The intervention group's fat mass decreased while their lean body mass increased (time effect p = 0.001 and p = 0.001, respectively). We found no interaction effect in body weight (p = 0.19), fat mass [p = 0.06, 6-months estimates -0.9 (95% CI -1.8 to -0.1)] and lean body mass (p = 0.92). Blood samples also failed to show a statistically significant interaction effect between time × group for HbA1c% (p = 0.64), Insulin (p = 0.33), Adiponectin (p = 0.87), Leptin (p = 0.52) and Triglycerides (p = 0.43). Only Adiponectin revealed significance in the time effect (p < 0.001) and Leptin in the group effect (p = 0.03). Dietary behavior during the study period was similar in patients in the intervention and control groups (interaction p = 0.81; group p = 0.09 and time p = 0.03). Discussion: Individualized online-based home training in postoperative cancer patients revealed only minor changes, with no group differences in body composition or metabolic laboratory parameters, which were predominantly in the reference range at baseline. More studies investigating effects of online-based home training on body composition and nutrition behavior are needed. Trial registration: https://drks.de/search/en/trial/DRKS00020499, DRKS-ID: DRKS00020499.

Effect of home-based online training and activity feedback on oxygen uptake in patients after surgical cancer therapy: a randomized controlled trial.

BACKGROUND: Exercise training is beneficial in enhancing physical function and quality of life in cancer patients. Its comprehensive implementation remains challenging, and underlying cardiopulmonary adaptations are poorly investigated. This randomized controlled trial examines the implementation and effects of home-based online training on cardiopulmonary variables and physical activity. METHODS: Of screened post-surgical patients with breast, prostate, or colorectal cancer, 148 were randomly assigned (1:1) to an intervention (2 × 30 min/week of strength-endurance training using video presentations) and a control group. All patients received activity feedback during the 6-month intervention period. Primary endpoint was change in oxygen uptake after 6 months. Secondary endpoints included changes in cardiac output, rate pressure product, quality of life (EORTC QoL-C30), C-reactive protein, and activity behavior. RESULTS: One hundred twenty-two patients (62 intervention and 60 control group) completed the study period. Change in oxygen uptake between intervention and control patients was 1.8 vs. 0.66 ml/kg/min (estimated difference after 6 months: 1.24; 95% CI 0.23 to 2.55; p = 0.017). Rate pressure product was reduced in IG (estimated difference after 6 months: - 1079; 95% CI - 2157 to - 1; p = 0.05). Physical activity per week was not different in IG and CG. There were no significant interaction effects in body composition, cardiac output, C-reactive protein, or quality of life. CONCLUSIONS: Home-based online training among post-surgery cancer patients revealed an increase of oxygen uptake and a decrease of myocardial workload during exercise. The implementation of area-wide home-based training and activity feedback as an integral component in cancer care and studies investigating long-term effects are needed. TRIAL REGISTRATION: DRKS-ID: DRKS00020499 ; Registered 17 March 2020.

Intensity-dependent cardiopulmonary response during and after strength training.

Whereas cardiopulmonary responses are well understood in endurance training, they are rarely described in strength training. This cross-over study examined acute cardiopulmonary responses in strength training. Fourteen healthy male strength training-experienced participants (age 24.5 ± 2.9 years; BMI 24.1 ± 2.0 kg/m2) were randomly assigned into three strength training sessions (three sets of ten repetitions) with different intensities (50%, 62,5%, and 75% of the 3-Repetition Maximum) of squats in a smith machine. Cardiopulmonary (impedance cardiography, ergo-spirometry) responses were continuously monitored. During exercise period, heart rate (HR 143 ± 16 vs. 132 ± 15 vs. 129 ± 18 bpm, respectively; p < 0.01; η2p 0.54) and cardiac output (CO: 16.7 ± 3.7 vs. 14.3 ± 2.5 vs. 13.6 ± 2.4 l/min, respectively; p < 0.01; η2p 0.56) were higher at 75% of 3-RM compared to those at the other intensities. We noted similar stroke volume (SV: p = 0.08; η2p 0.18) and end-diastolic volume (EDV: p = 0.49). Ventilation (VE) was higher at 75% compared to 62.5% and 50% (44.0 ± 8.0 vs. 39.6 ± 10.4 vs. 37.6 ± 7.7 l/min, respectively; p < 0.01; η2p 0.56). Respiration rate (RR; p = .16; η2p 0.13), tidal volume (VT: p = 0.41; η2p 0.07) and oxygen uptake (VO2: p = 0.11; η2p 0.16) did not differ between intensities. High systolic and diastolic blood pressure were evident (62.5% 3-RM 197 ± 22.4/108.8 ± 13.4 mmHG). During the post-exercise period (60 s), SV, CO, VE, VO2, and VCO2 were higher (p < 0.01) than during the exercise period, and the pulmonary parameters differed markedly between intensities (VE p < 0.01; RR p < 0.01; VT p = 0.02; VO2 p < 0.01; VCO2 p < 0.01). Despite the differences in strength training intensity, the cardiopulmonary response reveals significant differences predominantly during the post-exercise period. Intensity-induced breath holding induces high blood pressure peaks and cardiopulmonary recovery effects after exercise.

Long-term training improves clinical signs of periodontal disease in type 2 diabetic patients: a pilot trial.

BACKGROUND: Systemic inflammation is related to diabetes mellitus. Periodontal disease may be considered a local manifestation of systemic inflammation in association with diabetes mellitus. Physical activity may have a positive effect on inflammatory diseases. We investigated the effects of exercise training on periodontal inflammation in diabetic patients. METHODS: Out of 69 diabetic patients with periodontitis, 40 subjects participated in a recreational training, while 29 subjects performed no training. All underwent a periodontal examination before and after 6.14±1.24 months and completed a dental hygiene questionnaire. RESULTS: In the long-term training group the following parameters decreased: hemoglobin A1c from 6.7±1.0% to 6.3±0.7% (P<0.007), papillary bleeding score 3 by 60% (P<0.0003), and the mean of all probing pocket depths 4 - 6 mm by 40% (P<0.0001). No significant weight changes and no improvements in oral health behavior were observed in either of the groups. No correlation between hemoglobin A1c or weight and periodontal parameters was found. CONCLUSIONS: A six-months recreational training was independently related to improved clinical signs of periodontal disease in diabetic subjects.

Measurement of subcutaneous fat tissue: reliability and comparison of caliper and ultrasound via systematic body mapping.

Caliper and ultrasound (US) are used to measure subcutaneous fat tissue depth (SFT) and then to calculate total body fat. There is no evidence-based recommendation as to whether caliper or US are equally accurate. The aim of this paper was therefore to compare reliability of both methods. In this methodical study, 54 participants (BMI: 24.8 ± 3.5 kg/m2; Age: 43.2 ± 21.7 years) were included. Using systematic body mapping, the SFT of 56 areas was measured. We also analyzed 4 body sites via MRI. A comparison between caliper and US detected clear differences in mean SFT of all areas (0.83 ± 0.33 cm vs. 1.14 ± 0.54 cm; p < 0.001) showing moderate reliability (ICC 0.669, 95%CI: 0.625-0.712). US and MRI revealed in the abdominal area a SFT twice as thick as caliper (2.43 ± 1.36 cm vs. 2.26 ± 1.32 cm vs. 1.15 ± 0.66 cm; respectively). Caliper and US revealed excellent intrarater (ICC caliper: 0.944, 95%CI: 0.926-0.963; US: 0.934, 95%CI: 0.924-0.944) and good interrater reliability (ICC caliper: 0.794, 95%CI: 0.754-0.835; US: 0.825, 95%CI: 0.794-0.857). Despite the high reliability in measuring SFT that caliper and US show, our comparison of the two methods yielded clear differences in SFT, particularly in the abdominal area. In accuracy terms, US is preferable for most mapping areas.

Effects and duration of exercise-based prehabilitation in surgical therapy of colon and rectal cancer: a systematic review and meta-analysis.

PURPOSE: Functional capacity is an independent indicator of morbidity in colon and rectal cancer surgery. This systematic review describes the evaluated and synthesized effects of exercise prehabilitation depending on the duration of interventions on functional and postoperative outcomes in colon and rectal cancer surgery. METHODS: Three electronic databases (MEDLINE Pubmed, Web of Sciences, and Cochrane Registry) were systematically searched (January 2022) for controlled trials that investigated the effects of prehabilitation prior to colo-rectal cancer resection. RESULTS: Twenty-three studies were included in this systematic review and 14 in our meta-analyses assessing these outcomes: the 6 min walk distance (6MWD), postoperative overall complications, and length of stay (LOS). We observed a significant improvement in preoperative functional capacity as measured with 6MWD (mean difference: 30.8 m; 95% CI 13.3, 48.3; p = 0.0005) due to prehabilitation. No reductions in LOS (mean difference: - 0.27 days; 95% CI - 0.93, 0.40; p = 0.5) or postoperative overall complications (Odds ratio: 0.84; 95% CI 0.53, 1.31; p = 0.44) were observed. Prehabilitation lasting more than 3 weeks tended to lower overall complications (Odds ratio: 0.66; 95% CI 0.4, 1.1; p = 0.11). However, the prehabilitation time periods differed between colon and rectal carcinoma resections. CONCLUSION: Prehabilitation while the patient is preparing to undergo surgery for colorectal carcinoma improves functional capacity; and might reduce postoperative overall complications, but does not shorten the LOS. The studies we reviewed differ in target variables, design, and the intervention's time period. Multicenter studies with sufficient statistical power and differentiating between colon and rectal carcinoma are needed to develop implementation strategies in the health care system. REGISTRATION: PROSPERO CRD42022310532.

Exercise Capacity, Iron Status, Body Composition, and Mediterranean Diet in Patients with Chronic Heart Failure.

In addition to drug therapy, lifestyle modification, including physical activity, and nutrition management are an integral part of current guidelines for patients with chronic heart failure (CHF). However, evidence on which clinical parameters are most influenced by nutritional behaviour, exercise capacity, or iron status is scarce. For a multicenter intervention study, we included participants with diagnosed CHF (n = 165) as well as participants with elevated NT-proBNP values and risk factors for CHF (n = 74). Cardiorespiratory fitness was tested with a bicycle test, and adherence to the Mediterranean diet (MedDiet) was assessed with the MDS questionnaire. Our data strengthened previous results confirming that the higher a person's adherence to MedDiet, the higher the cardiorespiratory fitness and the lower the body fat. Furthermore, our results showed that anemia in patients with CHF has an impact in terms of cardiorespiratory fitness, and functional outcomes by questionnaire. Since our data revealed gaps in iron supply (37.9% with iron deficiency), malnutrition (only 7.8% with high adherence to MedDiet), and both symptomatic and non-symptomatic study participants failed to meet reference values for physical performance, we encourage the enforcement of the guidelines in the treatment of CHF more strongly.

The Influence of Customized Mouthguards on the Muscular Activity of the Masticatory Muscles at Maximum Bite and Motor Performance During Static and Dynamic Exercises.

BACKGROUND: Some studies have suggested that a mouthguard is a performance-enhancing device due to a remote voluntary contraction. The extent to which a mouthguard can induce this phenomenon, e.g., by potentially increasing biting, has not been clarified. This study's aim was to investigate the muscular activity of the maxillary and peripheral musculature and motor performance during a rest and exercise test. METHODS: Our study comprised 12 active, male, professional young handball players (age 18.83 ± 0.39 years). Their performance, electromyographic (EMG) muscle activity (Σ), and lateral deviation (Δ) of the masticatory and peripheral musculature were measured during rest in a maximum bite force measurement, one-legged stand, a kettlebell swing exercise and a jump test while wearing a customized mouthguard (CMG) or not wearing one (Co). RESULTS: Maximum bite force measurements did not differ significantly in their mean values of muscle activity (Σ) for the masseter and temporalis muscles (Co 647.6 ± 212.8 µV vs. CMG 724.3 ± 257.1 µV p = 0.08) (Co 457.2 ± 135.5 µV vs. CMG 426.6 ± 169.3 µV p = 0.38) with versus without CMG. We found no differences in the mean activation values during a one-legged stand, the kettlebell swing, and jump test (Σ) in any of the muscles tested. Lateral deviations (Δ) wearing a CMG were significantly less in the erector spinae during the kettlebell swing (Co 5.33 ± 3.4 µV vs. CMG 2.53 ± 1.8 µV p = 0.01) and countermovement jump (Co 37.90 ± 30.6 µV vs. CMG 17.83 ± 22.3 µV p = 0.03) compared to the performance without a CMG. Jump height, rotation moment, and balance were unchanged with versus without CMG. CONCLUSION: Our results at rest and during specific motor stress show no differences with or without a CMG. The improved peripheral muscular balance while wearing a CMG indicates improved muscular stabilization.

Decreased exercise capacity in young athletes using self-adapted mouthguards.

PURPOSE: There is evidence of both the preventive effects and poor acceptance of mouthguards. There are various effects on performance depending on the type of mouthguard model. Hemodynamic responses to wearing a mouthguard have not been described. The aim of this study was to investigate the effects of self-adapted mouthguards with breathing channels (SAMGvent). METHODS: In this randomized crossover study, 17 healthy, active subjects (age 25.12 ± 2.19 years) underwent body plethysmography and performed two incremental exertion tests wearing a (SAMGvent) and not wearing (CON) a mouthguard. Blood lactate, spirometrics, and thoracic impedance were measured during these maximum exercise tests. RESULTS: The mean values using a SAMGvent revealed significantly greater airway resistance compared to CON (0.53 ± 0.16 kPa·L-1 vs. 0.35 ± 0.10 kPa·L-1, respectively; p = < 0.01). At maximum load, ventilation with SAMGvent was less than CON (118.4 ± 28.17 L min-1 vs. 128.2 ± 32.16 L min-1, respectively; p = < 0.01). At submaximal loads, blood lactate responses with SAMGvent were higher than CON (8.68 ± 2.20 mmol·L-1 vs. 7.89 ± 1.65 mmol·L-1, respectively; p < 0.01). Maximum performance with a SAMGvent was 265.9 ± 59.9 W, and without a mouthguard was 272.9 ± 60.8 W (p < 0.01). Maximum stroke volume was higher using a SAMGvent than without using a mouthguard (138.4 ± 29.9 mL vs. 130.2 ± 21.2 mL, respectively; p < 0.01). CONCLUSION: Use of a self-adapted mouthguard led to increased metabolic effort and a significant reduction in ventilation parameters. Unchanged oxygen uptake may be the result of cardiopulmonary compensation and increased breathing efforts, which slightly affects performance. These results and the obvious preventive effects of mouthguards support their use in sports.

CRBP-TS - evaluation of a home-based training and health care program for colorectal, breast, and prostate cancer using telemonitoring and self-management: study protocol for a randomized controlled trial.

BACKGROUND: Physical training is recommended in various national and international guidelines for patients with cancer. Observational studies have shown that physical activity leads to reduced recurrence and mortality rates by 20-40% in colorectal, breast, and prostate cancer. Despite existing evidence, a systematic care structure is still lacking. The primary aim of this study is to implement and evaluate an online training platform to strengthen physical performance and patient empowerment after cancer surgery. METHODS: The evaluation will be conducted as a prospective multicenter randomized controlled trial with three subgroups (colorectal-, breast-, and prostate cancer). Each group will include 100 patients (total 300 patients including dropouts; clinical stages T1-3 and/or N+; M0 after surgery intervention) and the primary endpoint (13% increase in the maximal oxygen consumption during exercise) will be examined. The intervention group will receive a 6-month home-based online training (2-3 times per week strength-endurance training using video presentations), bidirectional activity feedback information, online communication, and online counseling. The control group (usual care) will be advised lifestyle improvement. In-hospital testing will be performed before, during, and after the intervention. In addition to cardiopulmonary capacity, tumor specific diagnostics (liquid biopsy, depression and fatigue assessment, metabolic and endothelial screening) will be applied. DISCUSSION: Due to the increasing incidence of cancer, associated with considerable mortality, morbidity and impaired quality of life, there is an imperative requirement for improved cancer care, of which structured physical training may become an integral component. TRIAL REGISTRATION: DRKS-ID: DRKS00020499 ; Registered 17 March 2020.

Effects of Custom-made Mouthguards on Cardiopulmonary Exercise Capacity.

The importance of using mouthguards as well as their low acceptance rate have been demonstrated. The aim of this study was to investigate the influence of customized mouthguards on hemodynamics.. This randomized crossover study used data from 13 subjects (23.5±1.4 years). The cardiopulmonary and metabolic parameters were observed during ergometer tests without mouthguard (control) in comparison to two types of mouthguards (with and normal without breathing channels). Maximum ventilation was significantly decreased with the normal mouthguard (113.3±30.00 l ∙ min-1) in contrast to the mouthguard with breathing channels (122.5±22.9 l ∙ min-1) and control (121.9±30.8 l ∙ min-1). Also the inspiration time was longer when using the normal mouthguard (0.70±0.11 s) compared to the mouthguard with breathing channels (0.63±0.11 s) and control (Co 0.64±0.10 s). Lactate was also increased under the influence of the mouthguard with breathing channels (10.72±1.4 mmol ∙ l-1) compared to the control (9.40±1.77 mmol ∙ l-1) and the normal mouthguard (9.02±1.67 mmol ∙ l-1). In addition, stroke volume kinetics (p=0.048) and maximum heart rates (p=0.01) show changes. Despite equal levels of oxygen uptake and performances under all three conditions, the use of mouthguards showed differences in cardiopulmonary parameters. The use of mouthguards during exercise does not affect physical performance and can be recommended for injury prevention.

A randomized crossover study on the effects of a custom-made mouthguard on cardiopulmonary parameters and cortisol differences in a validated handball specific course.

BACKGROUND: The importance of mouthguards for handball players has been proven however, most players are reluctant to use it. The impact on physical capacity is assessed heterogeneously in the literature. This study aimed to investigate the influence of custom-made mouthguards (CMGs) under handball specific stress. METHODS: This randomized crossover study used data from 15 youth professional handball players (age 17.0 ±0.5 years, weight 85.1±8.0 kg and height 191.2±6.9 cm) who performed a validated handball specific course and a lung function test. Pulmonary (spirometry), metabolic (blood lactate), and cortisol parameters were observed using a normal custom-made mouthguard without (nCMG) and with respiratory channels (CMGvent) in comparison to no mouthguard (Co). RESULTS: In resting spirometry, no differences in the parameter peak flow were observed using the CMGvent (9.57±1.59 l·s-1) and nCMG (9.17±1.03 l·s-1) in comparison to the Co (9.38±1.26 l·s-1). Under maximum stress, there were no differences in ventilation using CMGvent (151.2±15.64 L ·min-1), nCMG (148.6±12.51 l·min-1), and without mouthguard (145.8±14.32 l·min-1). Similar oxygen uptake was observed when using a CMGvent (45.51±4.14 L ·min-1·kg-1), nCMG (45.50±5.06 ml·min-1 ·kg-1), and without CMG (Co 43.90±4.02 mL ·min-1). The parameters of HR (CMGvent 185.2±11.63 bpm vs. Co 179.4±13.24 bpm p=0.46, nCMG 178.2±11.54 bpm vs. Co p=0.97; CMGvent vs. nCMG p=0.08) and in the blood lactate values (CMGvent: 9.66±2.3 mmol·l-1 vs. Co 9.07±2.1 mmol·l-1 p=0.63; nCMG 9.39±2.8 mmol·l-1 vs. Co p=0.87; CMGvent vs. nCMG p=0.91) displayed no differences. The cortisol production under stress showed no differences in the performance with the CMGvent (1.78±3.58 ng/ml), nCMG (0.74±4.52 ng/mL), and in the procedure without mouthguard (0.25. ±5.01 ng/ml). CONCLUSION: The results showed that under stress, there were no differences in the cortisol, ventilation, cardiac, and metabolic responses for all three conditions. Finally, the study shows that the use of a custom-made mouthguard does not negatively affect handball specific performance. Due to the preventive aspect of the mouthguard, the use of a custom-made mouthguard in handball is strongly recommended.

Effects of cardioselective beta-blockade on plasma catecholamines and performance during different forms of exercise.

BACKGROUND: Beta-blockers are still frequently used in cardiovascular diseases but may negatively influence the exercise capacity. The aim of the study was to analyze the effect of beta-blockade on physical performance and plasma level of catecholamine during different forms of exercise. METHODS: Ten prehypertensive athletes (age: 25.1±2.5 years, BMI: 24.4±2.4 kg/m2) performed repeated incremental exercise and steady-state-tests without and with the cardioselective beta-blocker bisoprolol (5mg/day). The cardiopulmonary, metabolic and the catecholamine responses were monitored. RESULTS: Beta-blocker treatment had no effect on maximum power output (Pmax), lactate and the maximal oxygen uptake (VO2max) (Pmax: 269.0±41.5 vs. 269.0±41.5 W; lactate: 8.7±2.6 vs. 8.6±3.2 mmol/L and VO2max: 3110±482 vs. 3077±425 mL/min, respectively; P not significant). Epinephrine and norepinephrine showed a similar exponential increase to maximum load with and without beta-blockade (epinephrinemax 1.92±1.8 vs. 1.93±1.3 nmol/L; P not significant; norepinephrinemax 12.78±7.9 vs. 16.89±12.2 nmol/L; P not significant). Beta-blockade lowered heart rate (HR) and systolic blood pressure (SBP) at rest and under maximum load (ΔHRrest: 10.6±11.1 bpm, P<0.05, ΔHR-Max: 27.8±6.6 bpm, P<0.01; ΔSBPrest: 19.4±9.3 mmHg, P<0.05, ΔSBPmax: 17.7±15.3 mmHg, P<0.01). The maximum oxygen pulse was higher in the tests performed under beta-blockade (IET: ΔVO2/HR: 3.1±2.2 mL/beat, P<0.01; SST: ΔVO2/HR: 3.4±1.4 mL/beat, P<0.001). CONCLUSIONS: Despite beta blockade and resulting differences in cardiopulmonary regulation during the exercise tests, the maximal oxygen capacity and the catecholamine concentration was similar. Higher exercise intensities (>50% Pmax) are associated with a marked increase in plasma catecholamines, which are not influenced by treatment with bisoprolol 5 mg/day.

Influence of a Vented Mouthguard on Physiological Responses in Handball.

Schulze, A, Laessing, J, Kwast, S, and Busse, M. Influence of a vented mouthguard on physiological responses in handball. J Strength Cond Res 34(7): 2055-2061, 2020-Mouthguards (MGs) improve sports safety. However, airway obstruction and a resulting decrease in performance are theoretical disadvantages regarding their use. The study aim was to assess possible limitations of a "vented" MG on aerobic performance in handball. The physiological effects were investigated in 14 male professional players in a newly developed handball-specific course. The measured values were oxygen uptake, ventilation, heart rate, and lactate. Similar oxygen uptake (V[Combining Dot Above]O2) values were observed with and without MG use (51.9 ± 6.4 L·min·kg vs. 52.1 ± 10.9 L·min·kg). During maximum load, ventilation was markedly lower with the vented MG (153.1 ± 25 L·min vs. 166.3 ± 20.8 L·min). The endexpiratory concentrations of O2 (17.2 ± 0.5% vs. 17.6 ± 0.8%) and CO2 (4.0 ± 0.5% vs. 3.7 ± 0.6%) were significantly lower and higher, respectively, when using the MG. The inspiration and expiration times with and without the MG were 0.6 ± 0.1 seconds vs. 0.6 ± 0.1 seconds and 0.7 ± 0.2 seconds vs. 0.6 ± 0.2 seconds (all not significant), respectively, indicating that there was no relevant airflow restriction. The maximum load was not significantly affected by the MG. The lower ventilation for given V[Combining Dot Above]O2 values associated with MG use may be an effect of improved biomechanics and lower respiratory drive of the peripheral musculature.

Prediction of Ergogenic Mouthguard Effects in Volleyball: A Pilot Trial.

Dental occlusion may affect static and dynamic balance. The effects of a mouthguard on pinpoint accuracy in volleyball were investigated in 28 players who completed a volleyball specific test. Also, masticatory electromyographic tests were performed. The mean pinpoint accuracy was significantly higher with a mouthguard (68.6±9.3 vs. 64.0±7.0 points from 100; p< 0.006). However, differential mouthguard effects were seen, and three subgroups were classified: Group 1 (markedly improved pinpoint accuracy), Group 2 (improved pinpoint accuracy), and Group 3 (reduced pinpoint accuracy). Group 1 had a high masseter resting tone, the masseter activity was low in MVC (maximum voluntary clench) and increased in BOC (maximum bite on cotton rolls; p< 0.04). This indicates a masseter weakness, which would be compensated by a mouthguard. In Group 2, the masseter activity in MVC was high-normal with an imbalance which was improved in BOC (p< 0.01), indicating a possible mouthguard benefit. In Group 3, MVC and BOC were in a high-normal range and showed no relevant deficits. In these subjects the mouthguard had adverse effects. Overall, subjects with masticatory deficits had a benefit from the mouthguard in pinpoint accuracy. Positive or negative mouthguard responders may be detectible from electromyographic tests.

Influence of Mouthguards on Physiological Responses in Rugby.

Mouthguards (MGs) are highly recommended in rugby. Airway obstruction and a resulting decrease in power output are potential disadvantages of their usage. The aim of the study was to assess possible limitations of "vented" (MG V ) and custom-made mouthguards (MG C ) on rugby players' performance. The MG effects were investigated in 13 male first-league rugby players ranging from 18-34 years old. First a lung function test was completed. Then a double incremental treadmill test was performed to measure maximum aerobic performance, ventilation, VO 2 , VCO 2 , heart rate, and lactate. Effects on sprint times (10 and 40 m) and countermovement jumps were also investigated. Peak flow values were significantly decreased with MG V by about 0.9 l/s. Neither ventilatory parameters nor oxygen uptake were affected by either of the mouthguards. Maximum lactate was significantly decreased in both MG types vs. no MG use. The maximum running velocity was similar in all tests. The aerobic energy turnover was moderately increased with the MG C and MG V . No effects were seen on sprint times or jump tests. Although neither type of mouthguard had a significant impact on maximum performance in treadmill running, the anaerobic energy turnover was decreased.