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Augmented tactile and performance feedback has been used to (re)train a modified lifting technique to reduce lumbar spine flexion, which has been associated with low back disorder development during occupational repetitive lifting tasks. However, it remains unknown if the presence of trunk extensor neuromuscular fatigue influences learning of this modified lifting technique. Therefore, we compared the effectiveness of using augmented tactile and performance feedback to reduce lumbar spine flexion during a repetitive lifting task, in both unfatigued and fatigued states. Participants completed repetitive lifting tests immediately before and after training, and 1-week later, with half of the participants completing training after fatiguing their trunk extensor muscles. Both groups demonstrated learning of the modified lifting technique as demonstrated by increased thorax-pelvis coordination variability and reduced lumbar range of motion variability; however, experiencing trunk extensor neuromuscular fatigue during lift (re)training may have slight negative influences on learning the modified lifting technique. Practitioner summary: An augmented lift (re)training paradigm using tactile cueing and performance feedback regarding key movement features (i.e. lumbar spine flexion) can effectively (re)train a modified lifting technique to reduce lumbar flexion and redistribute motion to the hips and knees. However, performing (re)training while fatigued could slightly hinder learning this lifting technique. [ABSTRACT FROM AUTHOR]

During play, ice hockey goaltenders routinely dehydrate through sweating and lose >2% body mass, which may impair thermoregulation and performance. Purpose: This randomized, crossover study examined the effects of mild dehydration on goaltender on-ice thermoregulation, heart rate, fatigue, and performance. Methods: Eleven goaltenders played a 70-minute scrimmage followed by a shootout and drills to analyze reaction time and movements. On ice, they either consumed no fluid (NF) and lost 2.4% (0.3%) body mass or maintained body mass with water (WAT) or a carbohydrate-electrolyte solution (CES). Save percentage, rating of perceived exertion, heart rate, and core temperature were recorded throughout, and a postskate questionnaire assessed perceived fatigue. Results: Relative to NF, intake of both fluids decreased heart rate (interaction: P = .03), core temperature (peak NF = 39.0°C [0.1°C], WAT = 38.6°C [0.1°C], and CES = 38.5°C [0.1°C]; P= .005), and rating of perceived exertion in the scrimmage (post hoc: R e .04), as well as increasing save percentage in the final 10 minutes of scrimmage (NF = 75.8% [1.9%], WAT = 81.7% [2.3%], and CES = 81.3% [2.3%], post hoc: P < .04). In drills, movement speed (post hoc: P < .05) and reaction time (post hoc: P < .04) were slower in the NF versus both fluid conditions. Intake of either fluid similarly reduced postskate questionnaire scores (condition: F<.0001). Only CES significantly reduced rating of perceived exertion in drills (post hoc: P < .0 5 ) and increased peak movement power versus NF (post hoc: P = .02). Shootout save percentage was similar between conditions (P = .37). Conclusions: Mild dehydration increased physiological strain and fatigue and decreased ice hockey goaltender performance versus maintaining hydration. Also, maintaining hydration with a CES versus WAT may further reduce perceived fatigue and positively affect movements. [ABSTRACT FROM AUTHOR]

Lifting with a flexed spine, especially near the end range of motion, has been identified as a potential risk factor for low back injury/pain. Therefore, individuals who develop discomfort from repetitive, prolonged and/or loaded flexed or slouched postures may benefit from a greater awareness of how to control and/or modify their spinal posture to avoid irritating their backs in these situations. This study was therefore designed to test the ability of spine-oriented verbal instructions to reduce intersegmental spine flexion during three lifting tasks. The lifts were first performed without any instructions on lifting technique. An audio recording was then played with instructions to limit bending in the lower back before repeating the lifts. Following the verbal instructions, maximum spine flexion angles significantly (p < 0.05) decreased at intersegmental levels in the lower thoracic and upper lumbar (T8/T9 to L2/L3) regions, but no significant changes were observed at the lower lumbar levels (L3/L4 to L5/S1). Thus, it is concluded that spine-oriented verbal instructions can decrease spine flexion during lifting; however, other cues/instructions may be required to target lower lumbar levels which have been identified as the most prone to injury/pain. [ABSTRACT FROM AUTHOR]