How does sleep help recovery from exercise-induced muscle injuries?

Objectives: Athletes and military personnel may experience sleep disturbances due to conditions of training and competitions or military missions/field operations. The risk of muscle injuries is greater for them when sleep duration decreases, and training load increases simultaneously, which can be exacerbated by fatigue. Accumulating evidence demonstrates that sleep extension improved performance, pain sensitivity and GH/IGF-I anabolic responses, which may be beneficial in accelerating recovery from muscle injuries.

Return to football training and competition after lockdown caused by the COVID-19 pandemic: medical recommendations.

The lockdown caused by the COVID-19 pandemic represents a great unknown regarding the physiological changes induced in elite football players. Although it will differ from country to country, the return to sport for professional football players will follow a forced lockdown never experienced and longer than the normal annual season break. Moreover, in addition to an obvious decrease in performance, the lockdown will possibly lead to an increase of the injury risk.

Medical recommendations for home-confined footballers' training during the COVID-19 pandemic: from evidence to practical application.

In early 2020, the world is facing a global emergency called COVID-19. Many professional footballers around the world are home confined. The maintenance of physical capacity is a fundamental requirement for the athlete, so the training sessions must be adapted to this unique situation.

Dual-polarization silicon nitride Bragg filters with low thermal sensitivity.

Wideband and polarization-independent wavelength filters with low sensitivity to temperature variations have great potential for wavelength division multiplexing applications. However, simultaneously achieving these metrics is challenging for silicon-on-insulator photonics technology. Here, we harness the reduced index contrast and the low thermo-optic coefficient of silicon nitride to demonstrate waveguide Bragg grating filters with wideband apolar rejection and low thermal sensitivity.

Sub-decibel silicon grating couplers based on L-shaped waveguides and engineered subwavelength metamaterials.

The availability of low-loss optical interfaces to couple light between standard optical fibers and high-index-contrast silicon waveguides is essential for the development of chip-integrated nanophotonics. Input and output couplers based on diffraction gratings are attractive coupling solutions. Advanced grating coupler designs, with Bragg or metal mirror underneath, low- and high-index overlays, and multi-level or multi-layer layouts, have proven less useful due to customized or complex fabrication, however.