BackgroundWhile physical activity has been shown to improve cognitive performance and well-being, office workers are essentially sedentary. We compared the effects of physical activity performed as (i) one bout in the morning or (ii) as microbouts spread out across the day to (iii) a day spent sitting, on mood and energy levels and cognitive function.MethodsIn a randomized crossover trial, 30 sedentary adults completed each of three conditions: 6 h of uninterrupted sitting (SIT), SIT plus 30 min of moderate-intensity treadmill walking in the morning (ONE), and SIT plus six hourly 5-min microbouts of moderate-intensity treadmill walking (MICRO). Self-perceived energy, mood, and appetite were assessed with visual analog scales. Vigor and fatigue were assessed with the Profile of Mood State questionnaire. Cognitive function was measured using a flanker task and the Comprehensive Trail Making Test. Intervention effects were tested using linear mixed models.ResultsBoth ONE and MICRO increased self-perceived energy and vigor compared to SIT (p < 0.05 for all). MICRO, but not ONE, improved mood, decreased levels of fatigue and reduced food cravings at the end of the day compared to SIT (p < 0.05 for all). Cognitive function was not significantly affected by condition.ConclusionsIn addition to the beneficial impact of physical activity on levels of energy and vigor, spreading out physical activity throughout the day improved mood, decreased feelings of fatigue and affected appetite. Introducing short bouts of activity during the workday of sedentary office workers is a promising approach to improve overall well-being at work without negatively impacting cognitive performance.Trial registration NCT02717377, registered 22 March 2016.

Biomechanical data on most bracing and protective equipment systems is lacking. To better understand the clinical success of counterforce bracing, a biomechanical analysis of braced and unbraced tennis players (serve and backhand strokes) was undertaken. Three-dimensional cinematography and electromyographic techniques were used. Three commonly used counterforce braces (lateral elbow, medial elbow, and radial-ulnar wrist) were compared with the unbraced condition. The overall results basically reveal positive biomechanical alterations in forearm muscle activity and angular joint acceleration dependent upon the brace and joint area analyzed.

Studies in anthropometry showed that more research is needed in the area of physical development and its relationship to playing tennis. Muscle activity patterns have been studied for the different strokes, although more data are available relative to the service. During the service, skilled tennis players were found to display more consistent muscular activity with shorter periods of activation, implying a higher level of coordination than less skilled players. In profiling players, positive correlations were found between tournament play and a number of fitness parameters. More research is needed to develop assessment measures that are tennis specific. Also, longitudinal studies will provide greater insight into player profiles. The general consensus on fitness development was that tennis players should incorporate flexibility, strength and endurance training in their programmes to minimise asymmetry and injuries, while simultaneously enhancing performance. Tennis was found to have both aerobic and anaerobic components, with the predominant energy supply coming from phosphagen energy system. These findings suggest training programmes should be designed specific to the actual energy and muscular demands of the game. The need for further research in all areas certainly still exists in order to gain a better understanding of the game.

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Because pigs frequently lose their footing and slip, it is important to understand slipping and its relation to different floor surfaces. An experiment was conducted to evaluate the gait and footing of young pigs walking on concrete floor surfaces having known friction characteristics and to determine critical skid resistance values in terms of the fitness of a concrete surface for flooring in pig quarters. Barrows were cinematographed with a high-speed 16-mm camera as they walked on various surfaces, and gait and footing were subsequently analyzed in motion studies. The six concrete floor test pads with different surface treatments (fine and coarse sand, fine and coarse broom, wood float and steel trowel) were evaluated for friction coefficient (skid resistance value) using a British pendulum tester both before and after pig tests. Leg angle, pastern angle and time variables were not related with average skid resistance value of the different floors. However, slip variables during a stride's stance phase per se were well related to surface-treatment differences in average skid resistance. Thus, the average skid resistance value generated by the British pendulum tester yielded one piece of objective information useful in assessing the fitness of concrete surfaces for floors in pig quarters. All the surfaces except the steel trowel surface had average skid resistance value of greater than 65 British pendulum number, and they all reduced a pig's chance of slipping relative to the steel trowel (less than 60 British pendulum number). The front leg was a more sensitive indicator than the rear of a floor's effect on the pig's gait and footing.