An electromyographic silent period can be observed preceding a rapid voluntary movement following the sustained contraction. This phenomenon has been called the “premotion silent period”, (p. s. p.) .
In the present study, relationship between frequency of the p. s, p. appearance and joint angle in the preparatory phase was examined. An elbow joint extension to visual stimulus was chosen fo the rapid voluntary movement. It was found that the p, s, p, appeared frequently at the elbow joint angle less than 80 degrees, and no noticeable change of the frequency was seen in this range. The frequency of the p, s. p. appearance exceeding 80 degrees had a tendency to decrease. The authors discussed the possibility of correlation between the p, s. p, appearance and activity of the muscle spindle.

An electromyographic silent period appears prior to initiation of a reaction movement. In order to estimate the mechanism of the silence, the statistical properties of the EMG before the onset of the phasic discharge were investigated. The EMG activity was processed as a stochastic process, and the statistical properties were analyzed. It was found that the mean of the rectified EMG decreased from 100 ms before the onset of the phasic discharge. As to the relationship between the silence and the depression of the EMG activity, it was estimated that the depressing influence was so remarkable that the silent period was observed.

The purpose of the present investigation was to examine the relationship between the open water swimming (OW) performance and the swimming speed at 2, 3, and 4 mmol/l of blood lactate concentration (SSLA2, SSLA3, and SSLA4) or the critical swimming speed (CSS). Six male collegiate swimmers performed the 10 kilometers of OW, as well as the multi-stage graded swimming test, in order to determine the SSLA2, SSLA3, SSLA4. Furthermore, the CSS was calculated based on the personal best records for 50 to 1500 meters of free-style indoor swimming. As a result, the SSLA2, SSLA3, SSLA4, and CSS corresponded to 102±6%, 106±6%, 110±7%, and 106±5% of the average swimming speed of the OW, respectively. Thereafter, the SSLA2 did not differ significantly in comparison to the average swimming speed of the OW, whereas the SSLA3, SSLA4, and CSS differed significantly with the average swimming speed of the OW (p＜0.05). Furthermore, the average swimming speed during the OW significantly correlated with the SSLA2, SSLA3, SSLA4, and CSS, respectively (p＜0.05). These results suggest that the OW performance significantly correlated with the swimming speed at 2 to 3 mmol/l of the blood lactate concentrations and CSS. Furthermore, regarding these parameters, the SSLA2 may accurately reflect the average swimming speed of OW.

The purpose of the present investigation was to examine the usefulness of the stepping rate for assessing the time spent in moderate to vigorous intensity physical activity (MVPA). In the present investigation, 11 young men wore two pedometers (LIFECORDER EX ; KZ, Walking Style ; WS) during controlled walking and jogging, as well as during free-living conditions for 3 days. In addition to the number of steps, the KZ determined the time spent in physical activity based on the intensity of the physical activity (light intensity physical activity (LPA); below 3 METs, and MVPA ; above 3 METs), and the stepping rate (≧60, ≧80, or ≧100 steps·min^-1). In contrast, the WS was defined as the physical activity for a stepping rate of 60 steps·min^-1 or more, continuously for longer than 10 min as the time spent in physical activity. Regarding the results, under continuous walking/jogging, the KZ-assessed LPA and MVPA well reflected the intensity of the physical activity. On the other hand, the WS accumulated the time spent in physical activity for longer than 90% of the actual exercise duration, regardless of the walking speed. Furthermore, the stepping rate corresponding to 3 METs was 102 steps·min^-1. Under free-living conditions, however, the KZ-detected MVPA differed significantly in comparison to the time of the physical activity as determined by the other algorithms, except for the time spent in a stepping rate of 80 or higher steps·min^-1. In conclusion, these results indicate that 100 steps·min^-1 is a useful stepping rate for the assessment of MVPA. However, under free living conditions, the stepping rate should be determined at a higher frequency than a one minute interval length in order to improve the accuracy of the MVPA assessment.

A Task Force team consisting of members from pharmaceutical companies --a central player to develop and implement RMP (Risk Management Plan)-- as well as health care professionals and members from academia was established in JSPE. The Task Force developed guidance for scientific approach to practical and ICH-E2E-compliant Pharmacovigilance Plan (PVP) stated in Japanese Risk Management Plan issued in April 2012 by the Ministry of Health, Labour and Welfare. The guidance contains the following topics.
1．Introduction: JSPE's activities and this task force's objectives for pharmacovigilance activities
2．How to select Safety Specification (SS) and describe its characteristics
・Selection of SS
・Characterization of SS
・Association with Research Questions (RQ)
3．How to define and describe RQ
・What is RQ ?
・RQ interpretation in other relevant guidelines
・Methodology to develop RQ for PVP with examples
・Best approach to integrating PVP for whole aspects of safety concern
4．How to optimize PVP for specific RQ
・Routine PVP or additional PVP ?
・Additional PVP design (RQ and study design, RQ structured with PICO or GPP's research objectives, specific aims, and rationale)
・Checklist to help develop PVP
5．Epilogue:
・What can/should be “Drug use investigation” in the context of ICH-E2E-compliant PVP.
・Significance of background incidence rate and needs for comparator group
・Infrastructure for the future PVP activities
6．Appendix: Checklist to help develop PVP activities in RMP
The task force team is hoping that this guidance help develop and conduct SS and PVP in accordance with ICH E2E, as stated in Japanese Risk Management Plan Guideline.