[Questionnaire Survey on IVR Dose Management in Tokai Region].

PURPOSE: National diagnostic reference levels in Japan 2020 (DRLs 2020) have been published. In the field of angiography, in addition to the fluoroscopic dose rate, incident air kerma at the patient entrance reference point displayed on the equipment (Ka,r: mGy) and air kerma-area product displayed on the equipment (PKA: Gycm2) were set. A questionnaire survey was conducted at each facility in the Tokai region to confirm the status of medical radiation dose control in the region. METHOD: A questionnaire survey was conducted at each facility in the Tokai region. The items were fluoroscopic dose rate in each area (head and neck, cardiac, chest and abdomen, and limbs), DA and DSA dose rates, and dose area product meter (Ka,r, PKA) for the main procedures in each area. RESULT: The median values in this study were lower than those in the DRLs 2020, indicating that appropriate dose control is being implemented in the Tokai region. The trends of fluoroscopic and radiographic dose rates were different in each area, and there was some variation among the facilities. CONCLUSION: We believe that the incorporation of fluoroscopic and radiographic dose rates by area into the DRLs will facilitate more appropriate dose control at each facility in the future.

The Effect of Augmented Feedback Type and Frequency on Velocity-Based Training-Induced Adaptation and Retention.

Nagata, A, Doma, K, Yamashita, D, Hasegawa, H, and Mori, S. The effect of augmented feedback type and frequency on velocity-based training-induced adaptation and retention. J Strength Cond Res 34(11): 3110-3117, 2020-The purpose of this study was to compare the benefits of 4 weeks of velocity-based training (VBT) using different augmented feedback (AugFb) types and the frequency of AugFb, and whether adaptations are retained 10 days post-training. Thirty-seven collegiate male rugby players were divided into groups that received immediate feedback (ImFb; n = 9), visual feedback (ViFb; n = 10), average feedback (AvgFb; n = 10) and no feedback (NoFb; n = 8) during each VBT session consisting of 3 sets of 5 repetitions of loaded jump squats. The ImFb group received AugFb regarding lifting velocity under loaded jump squats (LV-JS) after every jump, whereas LV-JS measures were averaged after each set of jumps and presented to the AvgFb group. The LV-JS were video-recorded and displayed as kinematic feedback for the ViFb group after each set, although NoFb was provided for the NoFb group. Loaded jump squats measures were reported at baseline, during each training session and 10 days post-training. Loaded jump squats measures were significantly greater for the ImFb Group compared with the other groups during a number of post-baseline time points (p ≤ 0.05). Furthermore, at 4 weeks of VBT and 10 days post-retention, effect size (ES) calculations showed that LV-JS measures were greater with moderate to large effects for the ImFb group compared with the NoFb (ES = 1.02-1.25), AvgFb (ES = 0.78-0.82) and ViFb (ES = 0.74-1.60), respectively. However, LV-JS measures were reduced with moderate to large effects 10 days post-retention for the ViFb (ES = -0.60) and NoFb (ES = -0.85) groups. Providing LV-JS feedback after each jump appears to optimize performance and should be considered as a training tool during VBT.

Resistance Training Acutely Impairs Agility and Spike-Specific Performance Measures in Collegiate Female Volleyball Players Returning from the Off-Season.

This study examined the acute effects of resistance training (RT) on volleyball-specific performance. Sixteen female volleyball players undertook their initial, pre-season RT bout. Countermovement jump (CMJ), delayed onset of muscle soreness (DOMS), and sport-specific performances (i.e., run-up jump, agility, and spiking speed and accuracy) were measured before, 24 (T24), and 48 (T48) hours after RT. A significant increase in DOMS was observed at T24 and T48 (~207.6% ± 119.3%; p < 0.05; ES = 1.8 (95% CI: 0.94-2.57)), whilst agility was significantly impaired at T48 (1.7% ± 2.5%; p < 0.05; ES = 0.30 (95% CI: -0.99-0.40)). However, there were no differences in CMJ (~-2.21% ± 7.6%; p > 0.05; ES = -0.11 (95% CI: -0.80-0.58)) and run-up jump (~-1.4% ± 4.7%; p > 0.05; ES = -0.07 (95% CI: -0.76-0.63)). Spiking speed was significantly reduced (-3.5% ± 4.4%; p < 0.05; ES = -0.28 (95% CI: -0.43-0.97)), although accuracy was improved (38.3% ± 81.4%: p < 0.05) at T48. Thus, the initial, preseason RT bout compromised agility and spiking speed for several days post-exercise. Conversely, spiking accuracy improved, suggesting a speed-accuracy trade-off. Nonetheless, at least a 48-h recovery may be necessary after the initial RT bout for athletes returning from the off-season or injury.

Postactivation potentiation effect of overloaded cycling on subsequent cycling Wingate performance.

BACKGROUND: This study examined the postactivation potentiation effects of overloaded cycling on subsequent Wingate performance. METHODS: Twenty anaerobic-trained men took part in this study. The participants were randomly allocated to complete three testing sessions separated by 7 days. Each week, participants either undertook a control session (CON) consisting of a sub-maximal cycling warm-up protocol followed by a Wingate Test, or separate sessions involving an overloaded 10-second cycling PAP protocol followed by a Wingate Test at 5 (T5) or 10 (T10) minutes, post-PAP protocol. Power outputs, cadence, total work, fatigue rate, heart rate and capillary lactate measures were recorded from each Wingate Test. Measures were compared between these sessions and between sessions that generated the greatest peak power output (Bestpeak-P) and mean power output (Bestmean-P) via repeated measures ANOVA with effect sizes (ES) also calculated. RESULTS: A significantly greater mean power output, total work and lactate levels were exhibited during the T10 condition compared to the CON condition (P<0.05, ES=1.57). Whilst not significant (P=0.06), a greater peak power output was exhibited during the Bestpeak-P condition compared to the CON condition with a large effect (ES=0.95). CONCLUSIONS: Results indicated that an overloaded cycling protocol increased power output and lactate measures in anaerobic-trained men during a 30-second, Wingate Test. Overloaded cycling enhances subsequent anaerobic performance and is therefore likely to provide greater training stimuli for anaerobically trained individuals.

Intra- and inter-rater reliability of isometric shoulder extensor and internal rotator strength measurements performed using a hand-held dynamometer.

[Purpose] The purpose of the present study was to establish the intra- and inter-rater reliability of measurement of extensor strength in the maximum shoulder abducted position and internal rotator strength in the 90° abducted and the 90° external rotated position using a hand-held dynamometer. [Subjects and Methods] Twelve healthy volunteers (12 male; mean ± SD: age 19.0 ± 1.1 years) participated in the study. The examiners were two students who had nonclinical experience with a hand-held dynamometer measurement. The examiners and participants were blinded to measurement results by the recorder. Participants in the prone position were instructed to hold the contraction against the ground reaction force, and peak isometric force was recorded using the hand-held dynamometer on the floor. Reliability was determined using intraclass correlation coefficients. [Results] The intra- and inter-rater reliability data were found to be "almost perfect". [Conclusion] This study investigated intra- and inter-rater reliability and reveald high reliability. Thus, the measurement method used in the present study can evaluate muscle strength by a simple measurement technique.

Same-session and between-day intra-rater reliability of hand-held dynamometer measurements of isometric shoulder extensor strength.

[Purpose] The purpose of present study was to establish the same-session and between-day intra-rater reliability of measurements of extensor strength in the maximum abducted position (MABP) using hand-held dynamometer (HHD). [Subjects] Thirteen healthy volunteers (10 male, 3 female; mean ± SD: age 19.8 ± 0.8 y) participated in the study. [Methods] Participants in the prone position with maximum abduction of shoulder were instructed to hold the contraction against the ground reaction force, and peak isometric force was recorded using the HHD on the floor. Participants performed maximum isometric contractions lasting 3 s, with 3 trials in one session. Between-day measurements were performed in 2 sessions separated by a 1-week interval. Intra-rater reliability was determined using intraclass correlation coefficients (ICC). Systematic errors were assessed using Bland-Altman analysis for between-day data. [Results] ICC values for same-session data and between-day data were found to be "almost perfect". Systematic errors not existed and only random error existed. [Conclusion] The measurement method used in this study can easily control for experimental conditions and allow precise measurement because the lack of stabilization and the impact of tester strength are removed. Thus, extensor strength in MABP measurement is beneficial for muscle strength assessment.