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Right ventricular structure and function in senior and academy elite footballers
Get PDFAims
Right ventricular (RV) adaptation is a common finding in the athlete's heart. The aim of this study was to establish the extent of RV structural and functional adaptation in elite and academy professional footballers compared to age‐matched controls.
Methods and Results
100 senior and 100 academy elite footballers, 20 senior and 19 academy age‐matched controls were recruited. All participants underwent 2D, Doppler, tissue Doppler and strain (ε) echocardiography of the right heart. Structural indices were derived and indexed allometrically for individual differences in body surface area. Standard RV function was assessed alongside peak RV ε and strain rate (SR). Senior football players had larger scaled RV structural parameters than players for the RV outflow (RVOTplax) (32.7±4.2 and 29.5±4.0 mm(m2)0.326, P<0.001), the proximal RV outflow (RVOT1) (26.6±3.5 and 24.7±3.9 mm(m2)0.335, P<0.001), the basal RV inflow (RVD1) (33.1±4.1 and 30.7±3.2 mm(m2)0.404, P=0.020), RV length (RVD3) (66.5±6.1 and 62.9±5.1 mm(m2)0.431, P<0.001) and RV diastolic area (RVDarea) (16.9±2.6 and 15.7±2.6 mm(m2)0.735, P<0.001). Both academy and senior football players demonstrated larger scaled structural RV parameters in comparison to age matched controls. Systolic SR (SRS) was lower in the senior players compared to academy players in the mid (‐1.52±0.49 and ‐1.41±0.34 l/s, P=0.019) and apical (‐1.97±0.74 and ‐1.72±0.42 l/s, P=0.025) wall regions, respectively.
Conclusion
RV structural adaptation occurs in both senior and academy football players with senior players having larger RV dimensions. Although senior players have slightly lower peak SRS than academy players, all global ε and SR are within normal ranges
Prescribing Target Running Intensities for High-School Athletes: Can Forward and Backward Running Performance Be Autoregulated?
Get PDFTarget running intensities are prescribed to enhance sprint-running performance and progress injured athletes back into competition, yet is unknown whether running speed can be achieved using autoregulation. This study investigated the consistency of running intensities in adolescent athletes using autoregulation to self-select velocity. Thirty-four boys performed 20 m forward running (FR) and backward running (BR) trials at slow, moderate and fast intensities (40–55%, 60–75% and +90% maximum effort, respectively) on three occasions. Absolute and relative consistency was assessed using the coefficient of variation (CV) and intraclass correlation coefficients (ICC). Systematic changes in 10 and 20 m performance were identified between trials 1–2 for moderate and fast BR (p ≤ 0.01) and during moderate BR over 20 m across trials 2–3 (p ≤ 0.05). However, comparisons between trials 2–3 resulted in low typical percentage error (CV ≤ 4.3%) and very good to excellent relative consistency (ICC ≥ 0.87) for all running speeds and directions. Despite FR being significantly (p ≤ 0.01) faster than BR at slow (26%), moderate (28%) and fast intensities (26%), consistency was similar in both running directions and strongest at the fastest speeds. Following appropriate familiarization, youth athletes may use autoregulation to self-select prescribed FR and BR target running intensitie
A framework for customer relationship management strategy orientation support in higher education institutions
Get PDFA number of generic Customer Relationship Management (CRM) implementation frameworks have been developed, yet no systematic framework has been developed to help HEIs orientate CRM strategy to align with university business strategies and stakeholder needs. This research iteratively develops the CRM Strategy Orientation Support (CRM-SOS) framework, which aims to support HEIs in orientating their strategic CRM system at the pre-implementation stage and align CRM strategy with the business strategy; thus, reducing the chance that HEIs will experience CRM implementation failure. To reach our proposed CRM-SOS framework, we employed Design Science Research (DSR) methodology steps by analysing UK HEIs specific CRM implementation case studies, conducting semi-structured HEIs-based interviews, followed by evaluation of the resulted framework by HEI Information Systems (IS) experts. We concluded with a new CRM-SOS framework for HEIs consisting of five stages. The framework can be used to personalise the stages until they fit the strategic outputs and match the top management KPIs. Although existing research agrees that intensive attention should be given to CRM planning, there is no consensus or developed framework, for use within HEIs, demonstrating how CRM strategy can be orientated to align with university strategies and customer needs
Social entrepreneurs in challenging places: A Delphi study of experiences and perspectives
Get PDFSocial Enterprises have grown in number and scope in response to reductions in state-provided welfare and increasing ambition to improve social conditions. While a range of issues have been identified in the literature as affecting the ability of Social Enterprises to successfully conduct their activities, there is currently a dearth of research into the relative influence of these factors. This study explores and ranks the challenges faced by social entrepreneurs in South Wales. Based on a Delphi study with 21 social entrepreneurs, government policy-developers and scholars, it presents a hierarchy of 14 factors, useful instruments for informing social entrepreneurs and policy-makers about the way social enterprises are managed, and how national and local policy should be developed. As part of this, the study also identifies four novel factors that affect the sustainability of social enterprises: ‘Professionalisation of Marketing’, ‘Perception of Validity’, ‘Leadership’ and ‘Situatedness’
Sport and exercise medicine consultants are reliable in assessing tendon neovascularity using ultrasound Doppler
Get PDFObjective: Several lower limb tendinopathy treatment modalities involve identification of pathological paratendinous or intratendinous neovascularisation to target proposed co-location of painful neoneuralisation. The ability to reliably locate and assess the degree of neovascularity is therefore clinically important. The Modified Ohberg Score (MOS) is frequently used to determine degree of neovascularity, but reliability has yet to be established among Sport and Exercise Medicine (SEM) consultants. This study aims to determine inter-rater and intra-rater reliability of an SEM consultant cohort when assessing neovascularity using the 5-point MOS.
Method: Eleven participants (7 male and 4 female) provided 16 symptomatic Achilles and patella tendons. These were sequentially examined using power Doppler (PD) enabled ultrasound (US) imaging by 6 SEM consultants who rated neovascular changes seen using the MOS. Representative digital scan images were saved for rescoring 3 weeks later. Inter-rater and intra-rater reliability of the MOS was examined using intraclass correlation coefficient (ICC) and Kappa Agreement scores.
Results: Neovascular changes were reported in 65.6% of 96 scans undertaken. ICC for inter-rater reliability was 0.86 and Fleiss Kappa 0.52. ICC for intra-rater reliability was 0.95 and Weighted Kappa 0.91.
Conclusions: Neovascular changes were present in two-thirds of symptomatic tendons. Excellent SEM consultant inter-rater and intra-rater reliability was demonstrated. These findings support the use of PD-enabled US to assess neovascularity by appropriately experienced SEM consultants. Furthermore, future interventional research using a similarly experienced SEM consultant cohort can be undertaken with assurance that assessment of neovascularity will be reliable
Feasibility and effects of intra-dialytic low-frequency electrical muscle stimulation and cycle training: A pilot randomized controlled trial
Get PDFBackground and objectives:
Exercise capacity is reduced in chronic kidney failure (CKF). Intra-dialytic cycling is beneficial, but comorbidity and fatigue can prevent this type of training. Low–frequency electrical muscle stimulation (LF-EMS) of the quadriceps and hamstrings elicits a cardiovascular training stimulus and may be a suitable alternative. The main objectives of this trial were to assess the feasibility and efficacy of intra-dialytic LF-EMS vs. cycling
Design, setting, participants, and measurements:
Assessor blind, parallel group, randomized controlled pilot study with sixty-four stable patients on maintenance hemodialysis. Participants were randomized to 10 weeks of 1) intra-dialytic cycling, 2) intra-dialytic LF-EMS, or 3) non-exercise control. Exercise was performed for up to one hour three times per week. Cycling workload was set at 40–60% oxygen uptake (VO2) reserve, and LF-EMS at maximum tolerable intensity. The control group did not complete any intra-dialytic exercise. Feasibility of intra-dialytic LF-EMS and cycling was the primary outcome, assessed by monitoring recruitment, retention and tolerability. At baseline and 10 weeks, secondary outcomes including cardio-respiratory reserve, muscle strength, and cardio-arterial structure and function were assessed.
Results:
Fifty-one (of 64 randomized) participants completed the study (LF-EMS = 17 [77%], cycling = 16 [80%], control = 18 [82%]). Intra-dialytic LF-EMS and cycling were feasible and well tolerated (9% and 5% intolerance respectively, P = 0.9). At 10-weeks, cardio-respiratory reserve (VO2 peak) (Difference vs. control: LF-EMS +2.0 [95% CI, 0.3 to 3.7] ml.kg-1.min-1, P = 0.02, and cycling +3.0 [95% CI, 1.2 to 4.7] ml.kg-1.min-1, P = 0.001) and leg strength (Difference vs. control: LF-EMS, +94 [95% CI, 35.6 to 152.3] N, P = 0.002 and cycling, +65.1 [95% CI, 6.4 to 123.8] N, P = 0.002) were improved. Arterial structure and function were unaffected.
Conclusions:
Ten weeks of intra-dialytic LF-EMS or cycling improved cardio-respiratory reserve and muscular strength. For patients who are unable or unwilling to cycle during dialysis, LF-EMS is a feasible alternative
Rating of perceived challenge as a measure of internal load for technical skill performance
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Right ventricular structure and function in the veteran ultramarathon runner: Is there evidence for chronic maladaptation?
Get PDFBackground: It has been proposed that chronic exposure to prolonged strenuous exercise may result in maladaptation of the right ventricle (RV). The aim was to establish RV structure and function, including septal insertion points, using conventional echocardiography and myocardial strain (ԑ) imaging in a veteran population of ultramarathon runners (UR) and age and sex-matched controls.
Methods: A retrospective study design provided 40 UR (>35 years old; mean ± SD training experience: 18 ± 12 years) and 24 sedentary controls whom had previously undergone conventional 2D, tissue Doppler and speckle tracking echocardiography to measure RV size and function. Peak RV ԑ and strain rate (SR) were assessed from the base, mid, and apical lateral wall. SR were assessed during systole (SRs’), early diastole (SRe’) and late diastole (SRa’). Regional assessment of RV insertion points were made at the basal inferoseptum and apical septum using left ventricular (LV) longitudinal ԑ, and at the anteroseptum and inferoseptum using LV circumferential and radial ԑ.
Results: All structural indices of RV size were significantly larger in UR. RV regional and global peak ԑ were not different between groups whereas basal RV SR was significantly lower in UR. UR had significantly higher peak LV circumferential ԑ (anteroseptum: -26 ± 8% vs -21 ± 6%; inferoseptum: -25 ± 6% vs -16 ± 9%), and higher peak LV longitudinal ԑ (apical septum; -28 ± 7% vs -22 ± 4%) compared to controls. There was regional heterogeneity in UR that was not observed in controls with significantly lower longitudinal ԑ at the basal inferoseptal insertion point when compared to the global ԑ (-19 ± 2% vs -22 ± 4%).
Conclusion: Myocardial ԑ imaging highlights no overt maladaptation in this cohort of veteran UR, although lower insertion point ԑ, compared to global ԑ, in UR may warrant further investigation
Interaction between Staphylococcus aureus and Pseudomonas aeruginosa is beneficial for colonisation and pathogenicity in a mixed-biofilm
Get PDFDebate regarding the co-existence of Staphylococcus aureus and Pseudomonas aeruginosa in wounds remains contentious, with the dominant hypothesis describing a situation akin to niche partitioning, whereby both microorganisms are present but occupy distinct regions of the wound without interacting. In contrast, we hypothesised that these microorganisms do interact during early co-colonisation in a manner beneficial to both bacteria. We assessed competitive interaction between S. aureus and P. aeruginosa in biofilm cultured for 24-72 h and bacterial aggregates analogous to those observed in early (<24h) biofilm formation, and interaction with human keratinocytes. We observed that S. aureus predominated in biofilm and non-attached bacterial aggregates, acting as a pioneer for the attachment of P. aeruginosa. We report for the first time that S. aureus mediates a significant (P<0.05) increase in the attachment of P. aeruginosa to human keratinocytes, and that P. aeruginosa promotes an invasive phenotype in S. aureus. We show that co-infected keratinocytes exhibit an intermediate inflammatory response concurrent with impaired wound closure that is in keeping with a sustained pro-inflammatory response which allows for persistent microbial colonisation. These studies demonstrate that, contrary to the dominant hypothesis, interactions between S. aureus and P. aeruginosa may be an important factor for both colonisation and pathogenicity in the chronic infected wound
Dietary nitrate lowers ambulatory blood pressure in treated, uncontrolled hypertension: a 7d, double-blind, randomized, placebo-controlled, crossover trial
Get PDFDietary nitrate has been shown to increase nitrate/nitrite levels and decrease blood pressure (BP) in multiple populations. There are few reports among hypertensives and these reports have provided conflicting evidence. We aimed to assess the effect of daily nitrate compared to placebo in subjects with uncontrolled hypertension.
On day 0, hypertensives wore an ambulatory BP monitor (ABPM) for 24h and blood was taken. Subjects were then randomized to 7d nitrate-rich beetroot juice (12.9mmol nitrate) followed by 7d nitrate-depleted beetroot juice (0.5mmol nitrate) or vice versa. ABPM and blood was assessed before and after both conditions.
20 subjects with treated yet uncontrolled hypertension entered and completed the trial (mean age = 62.5y, mean BMI = 30.7kg/m2). Baseline BP was 137/80 ± 7/7mmHg. Dietary nitrate was well tolerated and resulted in significantly increased plasma nitrite (p=0.0004) and decreased 24h SBP and DBP compared to placebo (-8mmHg; p =0.012 and -4mmHg; p=0.018 respectively).
Our results support the existing data suggesting an anti-hypertensive effect of dietary nitrate in treated yet uncontrolled hypertensives. Targeted dietary strategies appear promising contributors to BP control