Objectively Assessing the Effect of a Messenger-based Intervention to Reduce Sedentary Behavior in University Students: A Pilot Study.

AIM: Sedentary behavior poses a serious health risk. Students in particular are highly affected by prolonged, uninterrupted periods of sitting due to routines in everyday university life, such as attending lectures, self-study periods in the library, etc. Whereas university students are mostly young and therefore appear to be healthy, evidence-based consequences of prolonged sitting may come to pass in prospective times. Therefore, primary prevention must be initiated to shield university students from the occurrence of non-communicable diseases (NCDs). Consequently, the study aims to evaluate a messenger-based intervention designed to reduce sedentary time among university students. SUBJECTS AND METHODS: The effectiveness of the intervention was assessed in a randomized controlled trial with a convenience sample of thirty-four German university students. ActivPal devices (Pal Technologies Ltd., Glasgow) were applied to measure sedentary behavior objectively before and after a 3-week intervention of messages to interrupt sedentary time. An additional evaluation of the messages was carried out. RESULTS: Sedentary behavior decreased by about one hour in the intervention group. Explorative analysis shows a statistically significant, negative correlation between sedentary time at baseline and the change of sedentary behavior over time in the intervention group (r = - .81) indicating effectiveness of the intervention for the participants with the highest sedentary times at baseline. Additionally, the messages were considered appropriate by the participants. CONCLUSION: A reduction of sedentary time of one hour per day in the intervention group is practically significant. The current investigation had similar findings with prior studies where promising results for the reduction of sedentary behavior were observed through mobile-based interventions. The detected effects of the intervention in this pilot study demonstrate an opportunity for further research in this field.

Osteoarthritis and joint replacements of the lower limb and spine in ex-professional soccer players: A systematic review.

After a professional career as a soccer player, the risk of developing osteoarthritis (OA) in different joints of the spine and lower limb might be increased. The extent of this problem to date is not clear. Therefore, the aim of this systematic review is to summarize the prevalence of OA and joint replacement of the lower limb and spine in former professional soccer players. Relevant databases were searched with different combinations of key words: for example, OA, hip, knee, ankle, foot, joint replacement, soccer. Studies were included if they were original research, included a sample of former professional male soccer players, and had OA in the lower limb and/or spine; OA was diagnosed either through questionnaires or X-rays; and the article is in English, Dutch, or German. Sixteen studies with 1576 former players and 2153 control subjects were included in the review. Studies agreed that the prevalence of hip OA and hip replacements is significantly higher in former players compared to the control group. For the ankle and spine, there is only limited information, and for the prevalence of knee OA and knee replacement, the results are contradictory. The quality of the included studies was moderate. Future studies should have a prospective design to control for confounding factors, to identify possible risk factors and consequences for the individuals, and to be able to develop a prevention program.

Soccer fatigue, sprinting and hamstring injury risk.

The aim of this study was to investigate the effect of a multi-directional soccer-specific fatigue protocol on sprinting kinematics in relation to hamstring injury risk. Nine semi-professional soccer players (Mean +/- SD: Age: 21.3 +/- 2.9 year; Height 185.0 +/- 8.7 cm; Body Mass 81.6 +/- 6.7 kg) completed the SAFT(90); a multi-directional, intermittent 90 min exercise protocol representative of soccer match-play. The 10m sprint times and three-dimensional kinematic data were recorded using a high-speed motion capture system (Qualisys Track Manager) every 15 min during the SAFT(90). A significant time dependent increase was observed in sprint time during the SAFT(90) (P<0.01) with a corresponding significant decrease in stride length (P<0.01). Analysis of the kinematic sprint data revealed significantly reduced combined maximal hip flexion and knee extension angle, indicating reduced hamstring length, between pre-exercise and half-time (P<0.01) and pre-exercise and full-time (P<0.05). These findings revealed that the SAFT(90) produced time dependent impairments in sprinting performance and kinematics of technique which may result from shorter hamstring muscle length. Alterations in sprinting technique may have implications for the increased predisposition to hamstring strain injury during the latter stages of soccer match-play.