The Importance of Posture and Body Composition for The Stability and Selected Motor Abilities of Professional Handball Players.

The aim of the research was to analyze body composition, body posture and postural stability of professional male handball players and to determine the differences between players with correct and incorrect body posture, considering power of the lower limbs and agility, speed, and change of direction deficit. The study comprised 16 professional handball players. Body composition analysis was performed using the method of electrical bioimpedance. Body posture was examined using the Diers formetric III 4D optoelectronic method. Postural stability was tested via the Biodex Balance System. Players performed the following fitness tests assessing lower limb muscle power (LP, HS, CMJ), linear speed (SLS 20 m), and COD speed (Zig-Zag test, COD deficit). Only 31.25% of players demonstrated body posture with correct physiological curvatures, while 68.75% showed changes in body asymmetry. The group with correct body posture performed better in SLS 20m than the group with incorrect posture, yet in the Zig-Zag agility test, the difference in the results was not significant and this affected the COD deficit, which was higher. The vast majority of participants demonstrated postural defects and incorrect physiological curvatures of the spine. The occurrence of scoliotic posture was also observed. The body deflection angles indicated that athletes' postural stability was good. However, it is worth noting that the majority demonstrated a tendency towards asymmetrical body deflections to the right or to the left, backwards direction. One-sided sports specialization leads to disturbances in the statics of the body, therefore, it becomes necessary to include postural re-education exercises in training.

Parylene coatings on stainless steel 316L surface for medical applications--mechanical and protective properties.

The mechanical and protective properties of parylene N and C coatings (2-20 µm) on stainless steel 316L implant materials were investigated. The coatings were characterized by scanning electron and confocal microscopes, microindentation and scratch tests, whereas their protective properties were evaluated in terms of quenching metal ion release from stainless steel to simulated body fluid (Hanks solution). The obtained results revealed that for parylene C coatings, the critical load for initial cracks is 3-5 times higher and the total metal ions release is reduced 3 times more efficiently compared to parylene N. It was thus concluded that parylene C exhibits superior mechanical and protective properties for application as a micrometer coating material for stainless steel implants.