Publications by authors named "Masaaki Koido"
Article Synopsis
- The research explores how aerosol dynamics impact the risk of viral exposure during interactions, specifically using a human mannequin to simulate conditions.
- Results indicated that the peak risk of viral exposure occurs within 5 seconds during face-to-face encounters, regardless of ventilation status.
- Ventilated conditions significantly lower the risk of viral exposure compared to non-ventilated conditions, suggesting that managing interactions for a brief duration can reduce airborne virus transmission.
Objective: Adequate conditioning results from various physical, environmental, and psychological factors in sports activities. In this study, we aimed to clarify the concurrence and relevance of injuries, psychological problems, and sleep disturbance in university football (soccer) players. Biomechanical characteristics and risk factors for those injuries were also investigated.
View Article and Find Full Text PDFConcurrent Validity of GPS for Deriving Mechanical Properties of Sprint Acceleration.
Int J Sports Physiol Perform
January 2017
Purpose: To test the concurrent validity of data from 2 different global positioning system (GPS) units for obtaining mechanical properties during sprint acceleration using a field method recently validated by Samozino et al.
Methods: Thirty-two athletes performed maximal straight-line sprints, and their running speed was simultaneously measured by GPS units (sampling rate: 20 or 5 Hz) and either a radar or laser device (devices taken as references). Lower-limb mechanical properties of sprint acceleration (theoretical maximal force, theoretical maximal speed, maximal power) were derived from a modeling of the speed-time curves using an exponential function in both measurements.
Impairment of Sprint Mechanical Properties in an Actual Soccer Match: A Pilot Study.
Int J Sports Physiol Perform
October 2016
Purpose: To assess soccer-specific impairment of mechanical properties in accelerated sprinting and its relation with activity profiles during an actual match.
Methods: Thirteen male field players completed 4 sprint measurements, wherein running speed was obtained using a laser distance-measurement system, before and after the 2 halves of 2 soccer matches. Macroscopic mechanical properties (theoretical maximal horizontal force [F0], maximal horizontal sprinting power [Pmax], and theoretical maximal sprinting velocity [V0]) during the 35-m sprint acceleration were calculated from speed-time data.