Decreased exercise capacity in young athletes using self-adapted mouthguards

Comfort and wearability properties of custom-made and boil-and-bite mouthguards among basketball players: A randomized parallel arm clinical trial

BACKGROUND/AIM

Thermoplastic mouthguards have been a reliable means of protection against impacts and shocks for a century. Although orofacial injuries are prevalent among basketball players, many athletes still avoid using mouthguards due to concerns regarding impaired breathing, speech interference, and nausea. This study aims to compare basketball players' subjective assessments of two different thicknesses of custom-made mouthguards (MGs) with boil-and-bite MGs (B&B MG).

MATERIAL AND METHODS

A total of 60 systematically healthy male professional basketball players, without active orthodontic treatment, were enrolled and randomly assigned to three groups: Group 1 (received B&B MGs; n = 20), Group 2 (received custom-made MGs with a 3 mm thickness [ethyl vinyl asetat]; n = 20), and Group 3 (received custom-made MGs with a 5 mm thickness; n = 20). To evaluate MG comfort and usability, 12 key factors, including comfort, fit, stability, tiredness, thirsting, oral dryness, nausea, speaking, breathing, drinking, ease of wear and removal, and inclination to chew, were assessed. The athletes were made to rate these factors using a 10 cm-long Visual Analog Scale, measured at three-time intervals, and the values for both inter-group and intra-group were compared.

RESULTS

Data from 48 basketball players were retrieved, and data analysis revealed that B&B MGs had the least favorable parameter values. Among the B&B MG group, stability was reported to be poorer during the initial measurement (p < .05). In the second measurement, B&B MGs showed significantly lower values for comfort, stability, tiredness, speaking, and inclination to chew (p < .05). During the third measurement, the B&B MG group exhibited significantly reduced values for comfort, breathing, drinking, and speaking (p < .05). In contrast, no statistically significant difference was observed between 3 and 5 mm thickness MGs in these measurements.

CONCLUSIONS

Custom-made MGs with different thicknesses consistently outperformed B&B MGs in all measurements, indicating the potential to tailor MG thickness based on sport, age, professional level of athlete, and presence of other protective equipment. While custom-made mouthguards are considered the gold standard, dentists who provide B&B MGs can lead to cost savings while maintaining protection and encouraging athletes to use higher-quality custom-made mouthguards.

Faculty of sports science students, physical education teachers, and athletes' level of knowledge and attitude about mouthguards

OBJECTIVES

Traumatic dental injury occurs during sports competitions, training, and practice and can be prevented by the use of mouthguards. For this reason, this study aimed to evaluate the knowledge and attitudes of sports science faculty students, physical education teachers, and athletes about mouthguards.

METHODS

Five hundred thirty-two participants were reached via social media. In the questionnaire consisting of 20 questions, questions about the sociodemographic characteristics of the participants were asked in part 1, and questions about their level of knowledge and attitudes about the mouthguards were asked in part 2. Descriptive statistical analysis and a chi-square test were used to evaluate the data.

RESULTS

The number of people who think that mouthguards protect the athlete from traumatic dental injury is 381 (71.6%). The number of people who think that mouthguards affect the performance of the athlete is positively 228 (42.9%). To protect against traumatic dental injury, 51.48% of the participants preferred the custom-made; 39.3% of them preferred the boil-bite; 33.22% of them preferred the standard/stock type mouth guard; and 22.96% of them preferred the helmet, and 18.26% of them preferred the face mask.

CONCLUSIONS

The knowledge and attitude of sports science faculty students, physical education teachers, and athletes are low about mouthguards. Since these people who are engaged in sports have a high exposure to traumatic dental injuries, education should be given to increase their awareness about mouthguards.

Influence of wearing mouthguards on performance among athletes: A systematic review

OBJECTIVES

While the use of mouthguards is well established to prevent orofacial and dental trauma occurrence, limited evidence exists regarding their influence on athletic performance. The objective of this study was to conduct a systematic review of the literature to assess the effect of wearing mouthguards on athletic performance.

DESIGN

Systematic review.

METHODS

An extensive search was performed in the databases of PubMed/MEDLINE, Embase, Scopus and Cochrane Library for studies published up to August 2022. Only peer-reviewed studies involving humans in vivo and investigating the use of mouthguards on performance among athletes were included. Quality assessment was performed using the Cochrane Collaboration's risk of bias tool.

RESULTS

The initial query yielded 4785 citations, of which 41 studies met the inclusion criteria, comprising a total of 852 athletes. Overall, wearing mouthguards was found to improve athletic performance compared to the control group (without mouthguards). Custom-made mouthguards were found to be more effective in enhancing athletic performance compared to other types of mouthguards.

CONCLUSIONS

Wearing mouthguards should be advocated by athletes not only for the prevention of orofacial and dental trauma but also for their potential improvements in athletic performance in specific actions. However, caution must be exercised in interpreting these findings due to the variability in outcome measures and the lack of important methodological details.

Sports mouthguard overview: Materials, fabrication techniques, existing standards, and future research needs

Sports mouthguards are proven devices that reduce both the probability of and damage to orofacial tissues. While commonly used, clinicians may be unaware of the different sports mouthguard materials, proposed fabrication techniques, design recommendations, and newer digital fabrication methods. An overview of existing sports mouthguard standards is presented. It identifies that identify that the present requirements, while historically chosen in good faith, appear to be arbitrarily selected and not from clinical evidence-based derived data. In addition, identified sports mouthguard heterogeneous testing and data acquisition methods distinguishes that little possibility is afforded for the correlation of results. Furthermore, updated evidence with concussion prevention and/or alleviation is presented with evidence provided by sports mouthguard imbedded technology. The need for continued research is stressed to provide evidence-based data for concussion alleviation/prevention, digital fabrication methods and materials, and clinically based information for the revision of existing standards.

Locomotor-Respiratory Entrainment upon Phonated Compared to Spontaneous Breathing during Submaximal Exercise

Recently, increased attention to breathing techniques during exercise has addressed the need for more in-depth study of the ergogenic effects of breathing manipulation. The physiological effects of phonation, as a potential breathing tool, have not yet been studied. Thus, the aim of this study was to investigate the respiratory, metabolic and hemodynamic responses of phonated exhalation and its impact on locomotor-respiratory entrainment in young healthy adults during moderate exercise. Twenty-six young, healthy participants were subjected to peak expiratory flow (PEF) measurements and a moderate steady cycling protocol based on three different breathing patterns (BrP): spontaneous breathing (BrP1), phonated breathing pronouncing "h" (BrP2) and phonated breathing pronouncing "ss" (BrP3). The heart rate, arterial blood pressure, oxygen consumption, CO2 production, respiratory rate (RR), tidal volume (VT), respiratory exchange ratio and ventilatory equivalents for both important respiratory gasses (eqO2 and eqCO2) were measured (Cosmed, Italy) simultaneously during a short period of moderate stationary cycling at a predefined cadence. To evaluate the psychological outcomes, the rate of perceived exertion (RPE) was recorded after each cycling protocol. The locomotor-respiratory frequency coupling was calculated at each BrP, and dominant coupling was determined. Phonation gradually decreased the PEF (388 ± 54 L/min at BrP2 and 234 ± 54 L/min at BrP3 compared to 455 ± 42 L/min upon spontaneous breathing) and affected the RR (18.8 ± 5.0 min-1 at BrP2 compared to 22.6 ± 5.5 min-1 at BrP1 and 21.3 ± 7.2 min-1 at BrP3), VT (2.33 ± 0.53 L at BrP2 compared to 1.86 ± 0.46 L at BrP1 and 2.00 ± 0.45 L at BrP3), dominant locomotor-respiratory coupling (1:4 at BrP2 compared to 1:3 at BrP1 and BrP2) and RPE (10.27 ± 2.00 at BrP1 compared to 11.95 ± 1.79 at BrP1 and 11.95 ± 1.01 at BrP3) but not any other respiratory, metabolic or hemodynamic measures of the healthy adults during moderate cycling. The ventilatory efficiency was shown to improve upon dominant locomotor-respiratory coupling, regardless of BrP (eqO2 = 21.8 ± 2.2 and eqCO2 = 24.0 ± 1.9), compared to the other entrainment coupling regimes (25.3 ± 1.9, 27.3 ± 1.7) and no entrainment (24.8 ± 1.5, 26.5 ± 1.3), respectively. No interaction between phonated breathing and entrainment was observed during moderate cycling. We showed, for the first time, that phonation can be used as a simple tool to manipulate expiratory flow. Furthermore, our results indicated that in young healthy adults, entrainment, rather than expiratory resistance, preferentially affected ergogenic enhancement upon moderate stationary cycling. It can only be speculated that phonation would be a good strategy to increase exercise tolerance among COPD patients or to boost the respiratory efficiency of healthy people at higher exercise loads.

The impacts of surgical mask in young healthy subjects on cardiopulmonary function and muscle performance: a randomized crossover trial

Objective

To explore the impacts of surgical mask in normal subjects on cardiopulmonary function and muscle performance under different motor load and gender differences.

Design

Randomized crossover trial.

Setting

The Fifth Affiliated Hospital of Guangzhou Medical University, June 16th to December 30th, 2020.

Participants

Thirty-one college students (age: male 21.27 ± 1.22 years; female 21.31 ± 0.79 years) were recruited and randomly allocated in two groups.

Interventions

Group 1 first received CPET in the mask-on condition followed by 48 h of washout, and then received CPET in the mask-off condition. Group 2 first received CPET in the mask-off condition followed by 48 h of washout, then received CPET in the mask-on condition. The sEMG data were simultaneously collected.

Main outcome measures

The primary outcome was maximum oxygen uptake (VO₂ max) from CPET, which was performed on a cycle ergometer—this is the most important parameter associated with an individual’s physical conditioning. The secondary parameters included parameters reflecting exercise tolerance and heart function (oxygen uptake, anaerobic valve, maximum oxygen pulse, heart rate reserve), parameters reflecting ventilation function (respiration reserve, ventilation volume, tidal volume, breathing frequency), parameters reflecting gas exchange (end-tidal oxygen and carbon dioxide partial pressure, oxygen equivalent, carbon dioxide equivalent, and the relationship between dead space and tidal volume) and parameters reflecting skeletal muscle function [oxygen uptake, anaerobic valve, work efficiency, and EMG parameters including root mean square (RMS)].

Results

Comparing the mask-on and mask-off condition, wearing surgical mask had some negative effects on VO₂/kg (peak) and ventilation (peak) in both male and female health subjects [VO₂/kg (peak): 28.65 ± 3.53 vs 33.22 ± 4.31 (P = 0.001) and 22.54 ± 3.87 vs 26.61 ± 4.03 (P < 0.001) ml/min/kg in male and female respectively; ventilation (peak): 71.59 ± 16.83 vs 82.02 ± 17.01 (P = 0.015) and 42.46 ± 10.09 vs 53.95 ± 10.33 (P < 0.001) liter in male and female respectively], although, based on self-rated scales, there was no difference in subjective feelings when comparing the mask-off and mask-on condition. Wearing surgical masks showed greater lower limb muscle activity just in male subjects [mean RMS of vastus medialis (load): 65.36 ± 15.15 vs 76.46 ± 19.04 μV, P = 0.031]. Moreover, wearing surgical masks produced a greater decrease in △tidal volume (VTpeak) during intensive exercises phase in male subjects than in female [male − 0.80 ± 0.15 vs female − 0.62 ± 0.11 l P = 0.001].

Conclusions

Wearing medical/surgical mask showed a negative impact on the ventilation function in young healthy subjects during CPET, especially in high-intensity phase. Moreover, some negative effects were found both in ventilation and lower limb muscle actives in male young subjects during mask-on condition. Future studies should focus on the subjects with cardiopulmonary diseases to explore the effect of wearing mask.

Trial registration

Chinese Clinical Trial Registry (ChiCTR2000033449).

Effects of Wearing a 50% Lower Jaw Advancement Splint on Biophysical and Perceptual Responses at Low to Severe Running Intensities

Acute ergogenic effects of wearing occlusal splints have been reported for aerobic and anaerobic exercises, but the literature centered on performance improvement by using jaw repositioning splints is scarce. We aimed to analyze the effect of wearing a 50% lower jaw advancement splint on biophysical and perceptual responses at low to severe running intensities. Sixteen middle- and long-distance runners performed twice a 7 × 800 m intermittent running protocol (with 1 km·h⁻¹ increments and 30 s rest periods) in an outdoor track field using two lower intraoral splints (a placebo and a lower jaw advancer). These devices were custom manufactured for each participant and a randomized and repeated measure design was used to compare conditions. No differences between placebo and lower jaw advancer were found (e.g., 52.1 ± 9.9 vs. 53.9 ± 10.7 mL·kg⁻¹·min⁻¹ of oxygen uptake, 3.30 ± 0.44 vs. 3.29 ± 0.43 m of stride length and 16 ± 3 vs. 16 ± 2 Borg scores), but small effects were sometimes observed (e.g., 109.2 ± 22.5 vs. 112.7 ± 25.2 L·min⁻¹ of ventilation, ES = −0.42). Therefore, this jaw advancement splint had no substantial ergogenic effect on biophysical and perceptual responses when running at different intensities.