Tom Mercer

An investigation into the minimum accelerometry wear time for reliable estimates of habitual physical activity and definition of a standard measurement day in pre-school children.

The purpose of this study was to determine the number of hours and days of accelerometry data necessary to provide a reliable estimate of habitual physical activity in pre-school children. The impact of a weekend day on reliability estimates was also determined and standard measurement days were defined for weekend and weekdays.Accelerometry data were collected from 112 children (60 males, 52 females, mean (SD) 3.7 (0.7)yr) over 7 d. The Spearman-Brown Prophecy formula (S-B prophecy formula) was used to predict the number of days and hours of data required to achieve an intraclass correlation coefficient (ICC) of 0.7. The impact of including a weekend day was evaluated by comparing the reliability coefficient (r) for any 4 d of data with data for 4 d including one weekend day.Our observations indicate that 3 d of accelerometry monitoring, regardless of whether it includes a weekend day, for at least 7 h  d(-1) offers sufficient reliability to characterise total physical activity and sedentary behaviour of pre-school children. These findings offer an approach that addresses the underlying tension in epidemiologic surveillance studies between the need to maintain acceptable measurement rigour and retention of a representatively meaningful sample size.

RELIABILITY OF INDICES OF NEUROMUSCULAR LEG PERFORMANCE IN END-STAGE RENAL FAILURE

The purpose of this study was to examine the day-to-day reproducibility and single measurement reliability of peak force, time to half peak force and rate of force development indices of knee extension neuromuscular performance in patients with end-stage renal failure. Eleven self-selected patients (6 men, 5 women) receiving maintenance dialysis (dialysis history 67 +/- 42.8 month) completed 3 inter-day assessment sessions. Each comprised a standardized warm-up and 3 intermittent static maximal voluntary actions of the knee extensors of the preferred limb (45 degrees knee flexion angle [0 degrees = full knee extension]) using a specially-constructed dynamometer. Repeated measures ANOVA of coefficient of variation scores revealed significant differences between indices in their reproducibility across day-to-day trials. Post-hoc comparisons of group mean scores suggested that peak force (6.6 +/- 3.0%) offers significantly greater measurement reproducibility than time to half peak force (16.8 +/- 9.5%) or rate of force development (20.3 +/- 12.1%). Intraclass correlation coefficients and standard error of measurement scores showed that single-trial assessments of peak force, time to half peak force and rate of force development would demonstrate limited precision and capability to discriminate subtle intra-subject or inter-subject changes in neuromuscular performance.

Long-term pulse wave velocity outcomes with aerobic and resistance training in kidney transplant recipients - A pilot randomised controlled trial

Background This pilot study examined long-term pulse wave velocity (PWV) and peak oxygen uptake (VO2peak) outcomes following a 12-week moderate-intensity aerobic or resistance training programme in kidney transplant recipients. Method Single-blind, bi-centre randomised controlled parallel trial. 42 out of 60 participants completed a 9-month follow-up assessment (Aerobic training = 12, Resistance training = 10 and usual care = 20). Participants completed 12 weeks of twice-weekly supervised aerobic or resistance training. Following the 12-week exercise intervention, participants were transitioned to self-managed community exercise activity using motivational interviewing techniques. Usual care participants received usual encouragement for physical activity during routine clinical appointments in the transplant clinic. PWV, VO2peak, blood pressure and body weight were assessed at 12 weeks and 12 months, and compared to baseline. Results ANCOVA analysis, covarying for baseline values, age, and length of time on dialysis pre-transplantation, revealed a significant mean between-group difference in PWV of -1.30 m/sec (95%CI -2.44 to -0.17, p = 0.03) between resistance training and usual care groups. When comparing the aerobic training and usual care groups at 9-month follow-up, there was a mean difference of -1.05 m/sec (95%CI -2.11 to 0.017, p = 0.05). A significant mean between-group difference in relative VO2peak values of 2.2 ml/kg/min (95% CI 0.37 to 4.03, p = 0.02) when comparing aerobic training with usual care was revealed. There was no significant between group differences in body weight or blood pressure. There were no significant adverse effects associated with the interventions. Conclusions Significant between-group differences in 9-month follow-up PWV existed when comparing resistance exercise intervention with usual care. A long-term between-group difference in VO2peak was only evident when comparing aerobic intervention with usual care. This pilot study, with a small sample size, did not aim to elucidate mechanistic mediators related to the exercise interventions. It is however suggested that a motivational interviewing approach, combined with appropriate transition to community training programmes, could maintain the improvements gained from the 12-week exercise interventions and further research in this area is therefore warranted. Trial registration study number: ISRCTN43892586.

Fatigue interventions in long term, physical health conditions: A scoping review of systematic reviews.

Objective Fatigue is prominent across many long term physical health conditions. This scoping review aimed to map the fatigue intervention literature, to ascertain if certain interventions may be effective across conditions, and if novel interventions tested in specific long term conditions may be promising for other conditions. Methods Scoping review methodological frameworks were used. Electronic bibliographic databases were searched (inception to November 2016) for systematic reviews of fatigue interventions in long term conditions. Inclusion criteria were: long term physical health condition; review focus on fatigue management; objective and systematic review process; primary review outcome is fatigue. Articles focussing on surgical interventions or treatments thought to trigger fatigue were excluded. A narrative synthesis was performed. Results Of 115 full texts screened, 52 reviews were included. Interventions were categorised as pharmacological and non-pharmacological (exercise, psychological/behavioural and complementary medicine). Pharmacological interventions did not consistently demonstrate benefit, except for anti-TNFs and methylphenidate which may be effective at reducing fatigue. Non-pharmacological interventions such as graded exercise and fatigue-specific psychological interventions may be effective, but heterogeneous intervention components limit conclusions. ‘Complementary medicine’ interventions (e.g. Chinese herbal medicines) showed promise, but the possibility of publication bias must be considered. Conclusions Further research is necessary to inform clinical practice. The reported effectiveness of some interventions across inflammatory health conditions, such as anti-TNFs, aerobic exercise, and psychologically based approaches such as CBT, highlights a potential transdiagnostic avenue for fatigue management. More novel strategies that may be worth exploring include expressive writing and mindfulness, although the mechanisms for these in relation to fatigue are unclear. More work is needed to identify transdiagnostic mechanisms of fatigue and to design interventions based on these.

Test-retest reliability and minimal detectable change scores for the short physical performance battery, one-legged standing test and timed up and go test in patients undergoing hemodialysis

Functional tests are commonly used for chronic kidney disease (CKD) patients undergoing hemodialysis (HD). However, the relative and absolute reliability of such physical performance-outcome assessments must first be determined in specific patient cohorts. The aims of this study were to assess the relative and the absolute reliability of the Short Physical Performance Battery (SPPB), One-Legged Stance Test (OLST), and Timed Up and Go (TUG) test, as well as the minimal detectable change (MDC) scores for these tests in CKD patients receiving HD. Seventy-one end-stage CKD patients receiving HD therapy, aged between 21 and 90 years, participated in the study. The patients completed two testing sessions one to two weeks apart and performed by the same examiner, comprising the following tests: the SPPB (n = 65), OLST (n = 62), and TUG test (n = 66). High intraclass correlation coefficients (≥0.90) were found for all the tests, suggesting that their relative reliability is excellent. The MDC scores for the 90% confidence intervals were as follows: 1.7 points for the SPPB, 11.3 seconds for the OLST, and 2.9 seconds for the TUG test. The reliability of the SPPB, OLST, and TUG test for this sample were all considered to be acceptable. The MDC data generated by these tests can be used to monitor meaningful changes in the functional capacity of the daily living-related activity of CKD patients on HD.

Exercise rehabilitation for recovery from critical illness (Protocol)

Queen Margaret University, Edinburgh, UK. As part of an ongoing research education programme.