Relative age affects marathon performance in male and female athletes

Marathon runners are ranked in 5-year age groups. However the extent to which 5-year groupings facilitates equitable competition has not been evaluated. The aim of this study was to evaluate the effect of relative age in male and female marathon running. Marathon finishing times for the top ten male (aged 20-69 years) and female athletes (aged 20-64 years) were obtained from the 2013 New York and Chicago marathons. Intra-class and inter-class validity were evaluated by comparing performances within (intra-class) and between (inter-class) the 5-year age groups. Results showed intra-class effects in all male age groups over 50 years, in all female age groups over 40 years, and in male and female 20-24 age groups (p < 0.05). Inter-class differences existed between the 20-24 and 25-29 age groups in both males and females, between all male age groups over 50 years, and between all female age groups over 40 years (p < 0.05). This study provided the first evaluation of the effects of relative age in male and female marathon running. The results provide preliminary but compelling evidence that the relatively older male athletes in age groups over 50 years and the relatively older females in age groups over 40 years are competitively disadvantaged compared to the younger athletes in these age groups

Using Fitts Law’ to detect intentional misrepresentation

In paralympic classification, tests of impaired coordination (e.g., reciprocal tapping tasks) are effort dependent and therefore susceptible to intentional misrepresentation of abilities (IM)-deliberate exaggeration of impairment severity. The authors investigated whether reciprocal tapping tasks performed submaximally could be differentiated from tapping tasks performed with maximal voluntary effort, based on conformity with Fitts' law. Ten nondisabled participants performed 14 tapping tasks with their dominant hand on 3 separate occasions. Seven tasks were performed with MVE and the other 7 at speeds that were at least 20% slower. Results revealed that evaluating conformity with Fitts' law is a potentially valid method for objectively detecting IM during reciprocal tapping. Evaluation of sensitivity and specificity of the method is now warranted

Urokinase-type plasminogen activator and arthritis progression: role in systemic disease with immune complex involvement

INTRODUCTION: Urokinase-type plasminogen activator (u-PA) has been implicated in fibrinolysis, cell migration, latent cytokine activation, cell activation, T-cell activation, and tissue remodeling, all of which are involved in the development of rheumatoid arthritis. Previously, u-PA has been reported to play a protective role in monoarticular arthritis models involving mBSA as the antigen, but a deleterious role in the systemic polyarticular collagen-induced arthritis (CIA) model. The aim of the current study is to determine how u-PA might be acting in systemic arthritis models. METHODS: The CIA model and bone marrow chimeras were used to determine the cellular source of u-PA required for the arthritis development. Gene expression of inflammatory and destructive mediators was measured in joint tissue by quantitiative PCR and protein levels by ELISA. The requirement for u-PA in the type II collagen mAb-induced arthritis (CAIA) and K/BxN serum transfer arthritis models was determined using u-PA(-/-) mice. Neutrophilia was induced in the peritoneal cavity using either ovalbumin/anti-ovalbumin or the complement component C5a. RESULTS: u-PA from a bone marrow-derived cell was required for the full development of CIA. The disease in u-PA(-/-) mice reconstituted with bone marrow from C57BL/6 mice was indistinguishable from that in C57BL/6 mice, in terms of clinical score, histologic features, and protein and gene expression of key mediators. u-PA(-/-) mice were resistant to both CAIA and K/BxN serum transfer arthritis development. u-PA(-/-) mice developed a reduced neutrophilia and chemokine production in the peritoneal cavity following ovalbumin/anti-ovalbumin injection; in contrast, the peritoneal neutrophilia in response to C5a was u-PA independent. CONCLUSIONS: u-PA is required for the full development of systemic arthritis models involving immune complex formation and deposition. The cellular source of u-PA required for CIA is bone marrow derived and likely to be of myeloid origin. For immune complex-mediated peritonitis, and perhaps some other inflammatory responses, it is suggested that the u-PA involvement may be upstream of C5a signaling

Altered countermovement jump force profile and muscle- tendon unit kinematics following combined ballistic training

Combined heavy- and light-load ballistic training is often employed in high-performance sport to improve athletic performance and is accompanied by adaptations in muscle architecture. However, little is known about how training affects muscle-tendon unit (MTU) kinematics during the execution of a sport-specific skill (e.g., jumping), which could improve our understanding of how training improves athletic performance. The aim of this study was to investigate vastus lateralis (VL) MTU kinematics during a countermovement jump (CMJ) following combined ballistic training. Eighteen young, healthy males completed a 10-week program consisting of weightlifting derivatives, plyometrics, and ballistic tasks under a range of loads. Ultrasonography of VL and force plate measurements during a CMJ were taken at baseline, mid-test, and post-test. The training program improved CMJ height by 11 ± 13%. During the CMJ, VL's MTU and series elastic element (SEE) length changes and velocities increased from baseline to post-test, but VL's fascicle length change and velocity did not significantly change. It is speculated that altered lower limb coordination and increased force output of the lower limb muscles during the CMJ allowed more energy to be stored within VL's SEE. This may have contributed to enhanced VL MTU work during the propulsion phase and an improved CMJ performance following combined ballistic training

Group training exercise

Group exercise training is a popular training option for many reasons, largely related to the cost effectiveness of including groups of people together with one instructor (or multiple instructors) when compared to one-on-one instruction. The benefits of group exercise training are not only related to the health outcomes that are known to result from exercise in general but also include additional benefits due to the social aspects of the environment, and the potential improvements in adherence related to the social contract that is often formed between group members (Figure 13.1).Group training must adhere to the general principles of exercise prescription; however, there are certain additional concerns and considerations that must be accounted for in the group setting. This practical will cover the safety, instruction, delivery and adjustments that must be made to run an effective group session. The prevalence of group training in the health and fitness industry extends to the training of similar populations together. This might include participants with Parkinson’s disease, postpartum women and older individuals. In addition to groups that are formed by condition or population, there are also countless examples of group training by particular activities, such as Pilates, yoga, dance, sports and established commercial fitness paradigms. Many of the characteristics relevant to instructing group sessions should be consistent across group training as a whole; however, due to the significant scope that this entails, the focus of this practical is small group sessions of between 2 and 15 people, with session goals related to strength and cardiorespiratory fitness

Towards evidenced based classification in Paralympic athletics: Evaluating the valdity of activity limitation tests for use in classification of Paralympic running events

Objective: To classify Paralympic athletes, classifiers use test batteries to obtain an objective, pre-competition estimate of an athlete's training level. Five tests were evaluated to determine which combination explained the maximum variance in running performance in a non-disabled population. A non-disabled sample was required to permit psychometric evaluation of the tests without the confounding influence of impairment, and to provide an indication of normative performance

High performance testing for the elite mixed martial artist

Despite the increasing research interest and rapid growth in popularity of mixed martial arts (MMA), a detailed performance testing battery has yet to be presented in the scientific literature. A testing protocol is critical to assess the physical capacities of an elite athlete to determine the adaptations to the external training load and effectively direct targeted training interventions. Additionally, this strategy provides an objective determination of the athlete’s preparedness for high level competition. The purpose of this article is to review the physiological demands of MMA and propose a reliable and logically valid testing battery based on these demands. This testing battery is comprised of performance tests to be administered by the sports scientist on elite MMA athletes outside of a laboratory setting. It is proposed that power capabilities be assessed via the incremental load jump squat and ballistic bench press throw. Additionally, the medicine ball explosive power test is recommended as an alternative to these power assessments for strength coaches with minimal equipment. 1 repetition maximum back squat and bench press is suggested to quantify strength while a 40m sprint is described as an ideal method for determining short-term anaerobic performance in these athletes. Finally, a loaded prone bridge and Yo-Yo intermittent recovery level-2 test are presented to assess isometric strength endurance and intermittent anaerobic capacity respectively