GREEN EXERCISE AND CARDIOVASCULAR HEALTH: QUANTITATIVE EVIDENCE FROM A COMMUNITY CONSERVATION INTERVENTION IN THE UK

This paper aims to add to the fledgling body of work pertaining to the cardio-vascular benefits of self-motivated activity in naturalistic settings. Collecting results from a longitudinal study of a regional community conservation intervention in the UK, it is found that - across a wide range of age groups – simple engagement with a set of everyday horticultural tasks induces the exact levels of exercise that the medical and sport sciences define as optimal for the maintenance of everyday baseline fitness. It is further contended, in line with prior literature, that such capital-free initiatives, designed to improve a local social environment can, thereby, improve the core heath of individuals who may be averse to more conventional gym-type environments

GREEN EXERCISE AND CARDIOVASCULAR HEALTH: QUANTITATIVE EVIDENCE FROM A COMMUNITY CONSERVATION INTERVENTION IN THE UK

This paper aims to add to the fledgling body of work pertaining to the cardio-vascular benefits of self-motivated activity in naturalistic settings. Collecting results from a longitudinal study of a regional community conservation intervention in the UK, it is found that - across a wide range of age groups – simple engagement with a set of everyday horticultural tasks induces the exact levels of exercise that the medical and sport sciences define as optimal for the maintenance of everyday baseline fitness. It is further contended, in line with prior literature, that such capital-free initiatives, designed to improve a local social environment can, thereby, improve the core heath of individuals who may be averse to more conventional gym-type environments

Carrying shopping bags poses no additional fall risk to healthy older females as assessed by statistic and dynamic stability

Food shopping is an important aspect of maintaining independence and social interaction in older age (AgeUK, 2012, Food Shopping in Later Life). Carrying the shopping bags home, however, may pose higher fall risk. Carriage of UK-style shopping bag alters the body’s weight distribution by lowering the centre of gravity resulting in a more balanced static stance; however, when this stance is disturbed, it creates additional torsion which might make recovery difficult. The aim of the project, therefore, was to examine the effect of carrying shopping bags on static and dynamic postural stability in healthy older females aged over 65 years. Following institutional ethics approval, nine older females (aged 71 (s 5.9) years) performed both static and dynamic postural stability assessments carrying bags of varying loads and distributions (no bags, one 1.5-kg bag in each hand, one 3-kg bag in each hand, one 1.5-kg bag in preferred hand only, one 3-kg bag in preferred hand only; loads representing typical weight of essential shopping items) in a randomised order. For static postural stability assessment, participants stood quietly feet width apart on a force platform (AMTI, Massachusetts) for 30 s. Anteroposterior and mediolateral displacements, 95% ellipse area and sway velocity were calculated (BioAnalysis, Massachusetts). For dynamic postural stability, participants balanced on an uneven surface (Biodex, New York) for 30 s. Total anteroposterior and mediolateral displacements were calculated. Additionally, the load carried was quantified relative to handgrip strength (Takei Scientific Inst. Co. Ltd, Japan). A repeated measures analysis was used, and significance was set at P < 0.05. The heaviest load (3 kg in each hand, 6 kg in total) was 9.1% (range 7%–11%) of body mass. The heaviest load (3 kg in each hand) was 14.3% (range 9.8%– 22.8%) of handgrip strength. Neither static nor dynamic postural stability were affected by carrying shopping bags. The postural stability variables assessed have been previously shown to be related to fall risk (Fernie et al., 1982, Age and Ageing, 11, 11–16). The present findings suggest that despite the disturbance caused by the additional load, carrying shopping bags either in one hand only or in both hands does not increase the fall risk in older females, as seen from the similar static and dynamic postural stability scores across conditions. These results should help to alleviate concerns regarding safety of carrying shopping bags, thereby reducing social isolation, maintaining independence and increasing physical activity (Hornyak et al., 2013, Archives of Physical Medicine and Rehabilitation, 94, 2529–2534)

Evaluation of microbial communities associated with the liquid and solid phases of the rumen of cattle offered a diet of perennial ryegrass or white clover

Rumen microbiota plays an important role in animal productivity, methane production and health. Several different locations have been used to obtain rumen samples (i.e., liquid-phase samples, solid-phase samples, buccal swabs) in previous studies. Here we assess differences in the rumen microbiota between solid- and liquid-phases of the rumen under differing dietary conditions (white clover vs. perennial ryegrass); there were 4 sample types: liquid-associated/grass (LG), solid-associated/grass (SG), liquid-associated/clover (LC), and solid-associated/clover (SC). Four Holstein-Friesian cows were strip grazed on pure stands of perennial ryegrass or white clover in a change-over design experiment with 3 periods (each lasting for 3 weeks). Solid- and liquid- phase microbes were obtained following total rumen evacuation on the penultimate day of each period. DNA was extracted and multiplexed libraries sequenced using 16S next generation sequencing (Illumina MiSeq). Demultiplexed sequences underwent quality control and taxonomic profiles were generated for each sample. Statistical analysis for the effects of diet and phase was conducted both overall [using non-metric multidimensional scaling (NMDS) and diversity indices] and for individual taxa. Separation of both diet and phase was observed NMDS, with significant effects of diet (P < 0.001) and phase (P < 0.001) being observed. Regardless of diet, Prevotella was most abundant in the liquid samples. When assessing differences between phases, the majority of statistically significant taxa (predominantly from Archaea and the order Clostridiales) were found at higher relative abundances in solid-phase samples. Diversity (Shannon Index) was lower in the liquid-phase samples, possibly because of the higher relative abundance of Prevotella. A presence vs. absence approach, followed by Chi-squared testing, was adopted. Differences between phases (LG vs. LC, LC vs. LG, SG vs. SC, and SC vs. SG) and differences between phases for the clover diet (LC vs. SC and SC vs. LC) were significant (P < 0.001); differences between phases for the grass diet were non-significant. Sampling technique has a profound impact on reported microbial communities, which must be taken into consideration, particularly as archaea may be underestimated in the liquid-phase.</p

Effect of exercise training on neuromuscular function of elbow flexors and knee extensors of type 2 diabetic patients

Purpose: The effects of exercise training on neuromuscular function of arm and leg muscles in type 2 diabetic patients (T2D) was investigated. Methods: Eight T2D sedentary male patients (61.0 ± 2.3 years) and eight sedentary healthy age matched control subjects (H, 63.9 ± 3.8 years) underwent a 16-week supervised combined endurance and resistance exercise program. Before and after training, maximal isometric (MVIC), isokinetic (15, 30, 60, 120, 180, 240° s−1) torque and muscle endurance of the elbow flexors (EF) and knee extensors (KE) were assessed. Simultaneously, surface electromyographic signals from biceps brachii (BB) and vastus lateralis (VL) muscles were recorded and muscle fiber conduction velocity (MFCV) estimated. Results: Following training, maximal torque of the KE increased during MVIC and isokinetic contractions at 15 and 30° s−1 in the T2D (+19.1 ± 2.7% on average; p 0.05). MFCV recorded from the VL during MVIC and during isokinetic contractions at 15 and 30° s−1 increased (+11.2 ± 1.6% on average; p < 0.01), but in the diabetic group only. Muscular endurance was lower in T2D (20.1 ± 0.7 s) compared to H (26.9 ± 1.3 s), with an associated increase in the MFCV slope after training in the KE muscles only. Conclusion: The effect of a combined exercise training on muscle torque appears to be angular velocity-specific in diabetic individuals, with a more pronounced effect on KE muscles and at slow contraction velocities, along with an associated increase in the MFCV. MFCV appears to be a more sensitive marker than torque in detecting the early signs of neuromuscular function reconditioning

Validity and reliability of two field-based leg stiffness devices:Implications for practical use

Leg stiffness is an important performance determinant in several sporting activities. This study evaluated the criterion-related validity and reliability of 2 field-based leg stiffness devices, Optojump Next® (Optojump) and Myotest Pro® (Myotest) in different testing approaches. Thirty-four males performed, on 2 separate sessions, 3 trials of 7 maximal hops, synchronously recorded from a force platform (FP), Optojump and Myotest. Validity (Pearson's correlation coefficient, r; relative mean bias; 95% limits of agreement, 95%LoA) and reliability (coefficient of variation, CV; intraclass correlation coefficient, ICC; standard error of measurement, SEM) were calculated for first attempt, maximal attempt, and average across 3 trials. For all 3 methods, Optojump correlated highly to the FP (range r =.98-.99) with small bias (range 0.91-0.92, 95%LoA 0.86-0.98). Myotest demonstrated high correlation to FP (range r =.81-.86) with larger bias (range 1.92-1.93, 95%LoA 1.63-2.23). Optojump yielded a low CV (range 5.9% to 6.8%), high ICC (range 0.82-0.86), and SEM ranging 1.8-2.1 kN/m. Myotest had a larger CV (range 8.9% to 13.0%), moderate ICC (range 0.64-0.79), and SEM ranging from 6.3 to 8.9 kN/m. The findings present important information for these devices and support the use of a time-efficient single trial to assess leg stiffness in the field

Links between the rumen microbiota, methane emissions and feed efficiency of finishing steers offered dietary lipid and nitrate supplementation

peer-reviewedRuminant methane production is a significant energy loss to the animal and major contributor to global greenhouse gas emissions. However, it also seems necessary for effective rumen function, so studies of anti-methanogenic treatments must also consider implications for feed efficiency. Between-animal variation in feed efficiency represents an alternative approach to reducing overall methane emissions intensity. Here we assess the effects of dietary additives designed to reduce methane emissions on the rumen microbiota, and explore relationships with feed efficiency within dietary treatment groups. Seventy-nine finishing steers were offered one of four diets (a forage/concentrate mixture supplemented with nitrate (NIT), lipid (MDDG) or a combination (COMB) compared to the control (CTL)). Rumen fluid samples were collected at the end of a 56 d feed efficiency measurement period. DNA was extracted, multiplexed 16s rRNA libraries sequenced (Illumina MiSeq) and taxonomic profiles were generated. The effect of dietary treatments and feed efficiency (within treatment groups) was conducted both overall (using non-metric multidimensional scaling (NMDS) and diversity indexes) and for individual taxa. Diet affected overall microbial populations but no overall difference in beta-diversity was observed. The relative abundance of Methanobacteriales (Methanobrevibacter and Methanosphaera) increased in MDDG relative to CTL, whilst VadinCA11 (Methanomassiliicoccales) was decreased. Trimethylamine precursors from rapeseed meal (only present in CTL) probably explain the differences in relative abundance of Methanomassiliicoccales. There were no differences in Shannon indexes between nominal low or high feed efficiency groups (expressed as feed conversion ratio or residual feed intake) within treatment groups. Relationships between the relative abundance of individual taxa and feed efficiency measures were observed, but were not consistent across dietary treatments

Eye Movements Affect Postural Control in Young and Older Females

Visual information is used for postural stabilization in humans. However, little is known about how eye movements prevalent in everyday life interact with the postural control system in older individuals. Therefore, the present study assessed the effects of stationary gaze fixations, smooth pursuits, and saccadic eye movements, with combinations of absent, fixed and oscillating large-field visual backgrounds to generate different forms of retinal flow, on postural control in healthy young and older females. Participants were presented with computer generated visual stimuli, whilst postural sway and gaze fixations were simultaneously assessed with a force platform and eye tracking equipment, respectively. The results showed that fixed backgrounds and stationary gaze fixations attenuated postural sway. In contrast, oscillating backgrounds and smooth pursuits increased postural sway. There were no differences regarding saccades. There were also no differences in postural sway or gaze errors between age groups in any visual condition. The stabilizing effect of the fixed visual stimuli show how retinal flow and extraocular factors guide postural adjustments. The destabilizing effect of oscillating visual backgrounds and smooth pursuits may be related to more challenging conditions for determining body shifts from retinal flow, and more complex extraocular signals, respectively. Because the older participants matched the young group's performance in all conditions, decreases of posture and gaze control during stance may not be a direct consequence of healthy aging. Further research examining extraocular and retinal mechanisms of balance control and the effects of eye movements, during locomotion, is needed to better inform fall prevention interventions