The hamstring muscle group is the most frequently injured muscle group in non-contact muscle injuries in sports involving high-speed running. A total of 84% of hamstring injuries affect the biceps ...femoris (BF) muscle. Clinical assessments and magnetic resonance imaging (MRI) are routinely used for diagnosis and plan management. MRI-negative scans for clinically diagnosed hamstring injuries range from 14% to 45%. We tested the hypothesis that the functional differences between injured and non-injured BF assessed by tensiomyography can be used for diagnostic and classification purposes. We compared an injured group of 53 international-level soccer players and sprinters with 53 non-injured international-level soccer players and sprinters of both sexes. Comparing the injured vs. non-injured athletes and the left vs. right side in all of the athletes, we used the percentage of absolute differences in the BF contraction time (Tc) to classify non-injured and injured BF muscles. The receiver operating characteristic (ROC) curve and the area under the curve (AUC) and the precision−recall curve (PRC) were used to measure the classification accuracy and to identify cut-off limits using the Tc differences. There was a very high ROC AUC value of 0.981 (SE = 0.009, p < 0.000), with 98.11% of the injured muscles being correctly classified (cut-off point 12.50% on Tc differences), and an AUPRC value of 0.981, with association classification criteria at >9.87. Tensiomyography has a high predictive ability to discriminate between injured and non-injured BF non-invasively and functionally.
The aim of our study was to determine the self-reported incidence and prevalence of running-related injuries among participants of the 18
Ljubljana Marathon, and to identify risk factors for their ...occurrence.
A customized questionnaire was distributed over registration. Independent samples of t-test and chi-square test were used to calculate the differences in risk factors occurrence in the injured and non-injured group. Factors which appeared significantly more frequently in the injured group were included further into multiple logistic regression analysis.
The reported lifetime running injury (absence >2 weeks) incidence was: 46% none, 47% rarely, 4% occasionally, and 2% often. Most commonly injured body regions were: knee (30%), ankle and Achilles' tendon (24%), foot (15%), and calf (12%). Male gender, running history of 1-3 years, and history of previous injuries were risk factors for life-time running injury. In the season preceding the event, 65% of participants had not experienced any running injuries, 19% of them reported minor problems (max 2 weeks absenteeism), but 10% and 7% suffered from moderate (absence 3-4 weeks) or major (more than 4 weeks pause) injuries. BMI was identified as the solely risk factor.
This self-reported study revealed a 53% lifetime prevalence of running-related injuries, with the predominate involvement of knee, ankle and Achilles' tendon. One out of three recreational runners experienced at least one minor running injury per season. It seems that male gender, short running experience, previous injury, and BMI do increase the probability for running-related injuries.
In this viewpoint we make specific recommendations that can assist and make the return to sport/exercise as safe as possible for all those impacted – from the recreational athlete to the elite ...athlete. We acknowledge that there are varying rules and regulations around the world, not to mention the varying philosophies and numerous schools of thought as it relates to return to sport/exercise and we have been cognisant of this in our recommendations. Despite the varying rules and circumstances around the world, we believe it is essential to provide some helpful and consistent guidance for return to training and sport for sport and exercise physicians around the world at this most difficult time. The present viewpoint provides practical and medical recommendations on the resumption to sport process.
The aim of this overview was to recommend individual training plans using exercise prescriptions for adults and older adults during home-based rehabilitation. Over the last decade, many regular ...physical activity studies with large prospective cohorts have been conducted. Taken together, more than a million subjects have been included in these exercise studies. The risk of morbidity and mortality has been reduced by 30% to 40% as a result of exercise. These risk reductions hold true for many diseases, as well as for prevention and rehabilitation. Physical activity has also been in the treatment of many diseases, such as cardiopulmonary, metabolic or neurologic/psychiatric diseases, all with positive results. Based on these results, the prescription of exercise was developed and is now known as the exercise prescription for health in many European countries. Details have been published by the European Federation of Sports Medicine Associations (EFSMA). The exercise prescription is strongly recommended for inpatients, discharged patients and outpatients who have recovered from severe diseases. Rehabilitation improves general health, physical fitness, quality of life and may increase longevity of life.
The influence of hypoxia on heart rate variability (HRV) has been studied under resting conditions with mixed results. Differences have been found in physiological responses to normobaric versus ...hypobaric hypoxia. Our aim was to study the influence of hypobaric hypoxia on HRV during physical exercise to determine whether HRV changes due to the exercise-induced heart rate (HR) increase or whether hypoxia itself exerts an influence. We tested nine healthy non-acclimatised white males (age = 43 ± 7 years) at 400 and 4,200 m during exercises. At 400 m HRV was measured at 50% and 75% maximal oxygen uptake (VO
2
max). At 4,200 m HR was kept equal as during exercise at 400 m by adjusting the intensity of step testing. The Poincaré plot as a non-linear method of HRV analysis was used, where the shape of the ellipse depending on HRV is expressed by two parameters, SD1 and SD2 (correlating to parasympathetic activity and both sympathetic and parasympathetic activity, respectively). We established a decrease in SD2 and an insignificant decrease in SD1 at medium HR at 4,200 m compared to 400 m. Both parameters showed similar tendencies during high-intensity exercise. Our results indicate that hypobaric hypoxia itself exerts an influence on HRV at a moderate HR.
PDF
