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Hypertension is recognised as a leading attributable risk factor for cardiovascular disease and premature mortality. Global initiatives towards the prevention and treatment of arterial hypertension are centred around non-pharmacological lifestyle modification. Exercise recommendations differ between professional and scientific organisations, but are generally unanimous on the primary role of traditional aerobic and dynamic resistance exercise. In recent years, isometric exercise training (IET) has emerged as an effective novel exercise intervention with consistent evidence of reductions in blood pressure (BP) superior to that reported from traditional guideline-recommended exercise modes. Despite a wealth of emerging new data and endorsement by select governing bodies, IET remains underutilised and is not widely prescribed in clinical practice. This expert-informed review critically examines the role of IET as a potential adjuvant tool in the future clinical management of BP. We explore the efficacy, prescription protocols, evidence quality and certainty, acute cardiovascular stimulus, and physiological mechanisms underpinning its anti-hypertensive effects. We end the review with take-home suggestions regarding the direction of future IET research.

No previous studies have examined the effects of isometric training intensity upon resting blood pressure (BP). The aims of this study were (a) to compare the effects of leg isometric training, performed at two intensities, upon resting systolic-SBP, diastolic-DBP and mean arterial-MAP BP; and (b) to examine selected cardiovascular variables, in an attempt to explain any changes in resting BP following training. Thirty-three participants were randomly allocated to either control, high- (HI) or low-intensity (LI) training for 8 weeks. Participants performed 4 × 2 min exercise bouts 3× weekly. Resting BP was measured at baseline, 4-weeks and post-training. SBP, DBP and MAP fell significantly in both groups after training. Changes were –5.2 ± 4.0, –2.6 ± 2.9 and –2.5 ± 2.2 mmHg [HI]; –3.7 ± 3.7, –2.5 ± 4.8 and –2.6 ± 2.5 mmHg [LI] for SBP, DBP and MAP, respectively. There were no significant changes in BP at 4 weeks. No significant changes were observed in any of the other cardiovascular variables examined. These findings suggest that isometric training causes reductions in SBP, DBP and MAP at a range of exercise intensities, when it is performed over 8 weeks. Furthermore, it is possible to reduce resting BP using a much lower isometric exercise intensity than has previously been shown.

Purpose High intensity interval training (HIIT) has been shown to improve important health parameters, including aerobic capacity, blood pressure, cardiac autonomic modulation and left ventricular (LV) mechanics. However, adaptations in left atrial (LA) mechanics and aortic stiffness remain unclear. Methods Forty-one physically inactive males and females were recruited. Participants were randomised to either a 4-week HIIT intervention ( n  = 21) or 4-week control period ( n  = 20). The HIIT protocol consisted of 3 × 30-s maximal cycle ergometer sprints with a resistance of 7.5% body weight, interspersed with 2-min of active unloaded recovery, three times per week. Speckle tracking imaging of the LA and M-Mode tracing of the aorta was performed pre and post HIIT and control period. Results Following HIIT, there was significant improvement in LA mechanics, including LA reservoir (13.9 ± 13.4%, p  = 0.033), LA conduit (8.9 ± 11.2%, p  = 0.023) and LA contractile (5 ± 4.5%, p  = 0.044) mechanics compared to the control condition. In addition, aortic distensibility (2.1 ± 2.7 cm 2  dyn −1  10 3 , p  = 0.031) and aortic stiffness index (− 2.6 ± 4.6, p  = 0.041) were improved compared to the control condition. In stepwise linear regression analysis, aortic distensibility change was significantly associated with LA stiffness change R 2 of 0.613 ( p  = 0.002). Conclusion A short-term programme of HIIT was associated with a significant improvement in LA mechanics and aortic stiffness. These adaptations may have important health implications and contribute to the improved LV diastolic and systolic mechanics, aerobic capacity and blood pressure previously documented following HIIT.

Any polar-ordered material with a spatially uniform polarization field is internally frustrated: The symmetry-required local preference for polarization is to be nonuniform, i.e., to be locally bouquet-like or \"splayed.\" However, it is impossible to achieve splay of a preferred sign everywhere in space unless appropriate defects are introduced into the field. Typically, in materials like ferroelectric crystals or liquid crystals, such defects are not thermally stable, so that the local preference is globally frustrated and the polarization field remains uniform. Here, we report a class of fluid polar smectic liquid crystals in which local splay prevails in the form of periodic supermolecular-scale polarization modulation stripes coupled to layer undulation waves. The polar domains are locally chiral, and organized into patterns of alternating handedness and polarity. The fluid-layer undulations enable an extraordinary menagerie of filament and planar structures that identify such phases.

This paper considers international migration in the context of population ageing. In many Western countries, the search for appropriate responses to manage future population ageing and population decline has directed attention to international migration. It seems reasonable to believe that international migrants, mostly of young working age, can supply population deficits created by low birth rates, protect European society and economy from the economic costs of elderly dependency, and provide a workforce to care for the elderly. Particular prominence has been given to this option through the publicity attendant on a report from the UN Population Division in 2000 on 'replacement migration', which has been widely reported and widely misunderstood. Although immigration can prevent population decline, it is already well known that it can only prevent population ageing at unprecedented, unsustainable and increasing levels of inflow, which would generate rapid population growth and eventually displace the original population from its majority position. This paper reviews these arguments in the context of the causes and inevitability of population ageing, with examples mostly based on UK data. It discusses various options available in response to population ageing through workforce, productivity, pensions reform and other means. It concludes that there can be no 'solution' to population ageing, which is to a considerable degree unavoidable. However, if the demographic regime of the United Kingdom continues to be relatively benign, future population ageing can be managed with tolerable inconvenience without recourse to increased immigration for 'demographic' purposes. At present (2001), net immigration to the United Kingdom is already running at record levels and is now the main engine behind UK population and household growth. By itself, population stabilization, or even mild reduction, is probably to be welcomed in the United Kingdom, although the issue has attracted little attention since the 1970s.

We give an efficient method based on minimal deterministic finite automata for computing the exact distribution of the number of occurrences and coverage of clumps (maximal sets of overlapping words) of a collection of words. In addition, we compute probabilities for the number of h-clumps, word groupings where gaps of a maximal length h between occurrences of words are allowed. The method facilitates the computation of p-values for testing procedures. A word is allowed to contain other words of the collection, making the computation more general, but also more difficult. The underlying sequence is assumed to be Markovian of an arbitrary order.

The aim of the study was to assess the reliability of sprint performance in both field and laboratory conditions. Twenty-one male (mean ± s: 19 ± 1 years, 1.79 ± 0.07 m, 77.6 ± 7.1 kg) and seventeen female team sport players (mean ± s: 21 ± 4 years, 1.68 ± 0. 07 m, 62.7 ± 4.7 kg) performed a maximal 20-metre sprint running test on eight separate occasions. Four trials were conducted on a non-motorised treadmill in the laboratory; the other four were conducted outdoors on a hard-court training surface with time recorded by single-beam photocells. Trials were conducted in random order with no familiarisation prior to testing. There was a significant difference between times recorded during outdoor field trials (OFT) and indoor laboratory trials (ILT) using a non-motorised treadmill (3.47 ± 0.53 vs. 6.06 ±1.17s; p < 0.001). The coefficient of variation (CV) for time was 2.55-4.22% for OFT and 5.1-7.2% for ILT. During ILT peak force (420.9 ± 87.7N), mean force (147.2 ± 24.7N), peak power (1376.8 ± 451.9W) and mean power (514.8 ± 164.4W), and were measured. The CV for all ILT variables was highest during trial 1-2 comparison. The CV (95% confidence interval) for the trial 3-4 comparison yielded: 9.4% (7.7-12. 1%), 7.9% (6.4-10.2%), 10.1% (8.2-13.1%) and 6.2% (5.1-8.0%) for PF, MF, PP and MP and respectively. The results indicate that reliable data can be derived for single maximal sprint measures, using fixed distance protocols. However, significant differences in time/speed over 20-m exist between field and laboratory conditions. This is primarily due to the frictional resistance in the non- motorised treadmill. Measures of force and power during ILT require at least 3 familiarisations to reduce variability in test scores. Key pointsReliable data can be derived from single maximal sprint measures in both indoor and outdoor environments using fixed distance protocols.There may be significant time differences to complete fixed distance trials between the two environments.Measures of mean force, peak force and peak power during indoor trials may require multiple trials to reduce variability in test scores.

The placebo effect, a positive outcome resulting from the belief that a beneficial treatment has been received, is widely acknowledged but little understood. It has been suggested that placebo responsiveness, the degree to which an individual will respond to a placebo, might vary in the population. The study aimed to identify placebo-responsive participants from a previously published paper that examined the effects of caffeine and placebos on cycling performance. A quantitative model of placebo responsiveness was defined. 14 male participants were subsequently classified as either placebo responsive or non-responsive. Interviews were conducted to corroborate these classifications. Secondary quantitative analyses of performance data were conducted to identify further placebo responses. Finally, the five factor model of personality was used to explore relationships between personality and placebo responsiveness. Overall, 5 of 14 participants were classified as placebo responsive. Performance data suggested that 2 participants were placebo responsive whilst 12 were not. Interview data corroborated experimental data for these participants and for 9 of the remainder, however it suggested that the remaining 3 had experienced placebo effects. Secondary quantitative analysis revealed that performance for these 3 participants, whilst no better than for non-responsive participants, was associated with substantially increased oxygen uptake in the 2 conditions in which participants believed caffeine had been administered (7.0% ± 15.1; 95% confidence intervals -2.6 to 16.7, and 6.0% ± 15.4; -3.9 to 15.9 respectively). Finally, data suggested that the personality factors of extroversion, agreeableness, openness and neuroticism may relate to placebo responding. Placebo effects such as pain tolerance and fatigue resistance might be experienced by a percentage of participants but might not always be manifest in objective measures of performance. Key pointsBeliefs can have both positive (placebo) and negative (nocebo) effectsPlacebo effects may be experienced both objectively and subjectivelyCertain personality traits may be related to placebo respondingA multi-method approach may best elucidate placebo effects in sport.

The UK Trial of Early Detection of Breast Cancer (TEDBC) is a non-randomised study, which was set up in 1979 to investigate the effect of screening and education about breast self-examination on breast-cancer mortality. We report mortality results after 16 years of follow-up, including results by age at trial entry. Eight centres (two screening, two breast self-examination, and four comparison) in England and Scotland recruited women aged 45-64 years into the initial cohort, with women reaching age 45 years during the 7-year study period included in later cohorts. The observed number of deaths from breast cancer in each centre was compared with the expected number, which was calculated by Poisson regression model; expected numbers were adjusted for pretrial breast-cancer mortality. Results were analysed by 5-year age-groups, and for women aged 45-46 years and 47-49 years at entry. Breast-cancer mortality was 27% lower (rate ratio 0.73 [95% CI 0.63-0.84]), adjusted for pretrial rates, in cohort 1 in the two screening centres combined than in the comparison centres. No reduction in mortality in the two breast self-examination centres combined was seen (rate ratio 0.99 [0.87-1.12]). The mortality reduction in the screening centres did not differ significantly across age-groups; a 35% reduction was seen in women in all cohorts aged 45-46 years at entry (rate ratio 0.65 [0.50-0.86]). Results were similar when deaths were restricted to those in patients diagnosed within 10 years of trial entry. The results from TEDBC support those from randomised trials in Edinburgh and elsewhere, and show that a reduction in breast-cancer mortality resulting from screening can be achieved in the UK. There was no evidence of less benefit in women aged 45-46 years at the start of screening; the effect of screening in this age-group begins to emerge after 3-4 years.

The aim of this study was to evaluate the impact of a novel crank system on laboratory time-trial cycling performance. The Rotor system makes each pedal independent from the other so that the cranks are no longer fixed at 180°. Twelve male competitive but non-elite cyclists (mean ± s: 35 ± 7 yr, Wmax = 363 ± 38 W, VO2peak = 4.5 ± 0.3 L·min(-1)) completed 6-weeks of their normal training using either a conventional (CON) or the novel Rotor (ROT) pedal system. All participants then completed two 40.23-km time-trials on an air-braked ergometer, one using CON and one using ROT. Mean performance speeds were not different between trials (CON = 41.7 km·h(-1) vs. ROT = 41.6 km·h(-1), P > 0.05). Indeed, the pedal system used during the time-trials had no impact on any of the measured variables (power output, cadence, heart rate, VO2, RER, gross efficiency). Furthermore, the ANOVA identified no significant interaction effect between main effects (Time-trial crank system*Training crank system, P > 0.05). To the authors' knowledge, this is the first study to examine the effects of the Rotor system on endurance performance rather than endurance capacity. These results suggest that the Rotor system has no measurable impact on time-trial performance. However, further studies should examine the importance of the Rotor 'regulation point' and the suggestion that the Rotor system has acute ergogenic effects if used infrequently. Key pointsThe Rotor crank system does not improve gross efficiency in well-trained cyclists.The Rotor crank system has no measurable impact on laboratory 40.23-km time-trial performance.A 6-week period of familiarisation does not increase the effectiveness of the Rotor crank system.