Physiological effects of microcurrent and its application for maximising acute responses and chronic adaptations to exercise.

Microcurrent is a non-invasive and safe electrotherapy applied through a series of sub-sensory electrical currents (less than 1 mA), which are of a similar magnitude to the currents generated endogenously by the human body. This review focuses on examining the physiological mechanisms mediating the effects of microcurrent when combined with different exercise modalities (e.g. endurance and strength) in healthy physically active individuals. The reviewed literature suggests the following candidate mechanisms could be involved in enhancing the effects of exercise when combined with microcurrent: (i) increased adenosine triphosphate resynthesis, (ii) maintenance of intercellular calcium homeostasis that in turn optimises exercise-induced structural and morphological adaptations, (iii) eliciting a hormone-like effect, which increases catecholamine secretion that in turn enhances exercise-induced lipolysis and (iv) enhanced muscle protein synthesis. In healthy individuals, despite a lack of standardisation on how microcurrent is combined with exercise (e.g. whether the microcurrent is pulsed or continuous), there is evidence concerning its effects in promoting body fat reduction, skeletal muscle remodelling and growth as well as attenuating delayed-onset muscle soreness. The greatest hindrance to understanding the combined effects of microcurrent and exercise is the variability of the implemented protocols, which adds further challenges to identifying the mechanisms, optimal patterns of current(s) and methodology of application. Future studies should standardise microcurrent protocols by accurately describing the used current [e.g. intensity (µA), frequency (Hz), application time (minutes) and treatment duration (e.g. weeks)] for specific exercise outcomes, e.g. strength and power, endurance, and gaining muscle mass or reducing body fat.

Acceptability and Feasibility of an Isometric Resistance Exercise Program for Abdominal Cancer Surgery: An Embedded Qualitative Study.

Although it is recognized in the early stages of cancer recovery that changes in lifestyle including increases in physical activity improves physical function, there are no clear findings whether low versus moderate intensity activity or home or gym exercise offer optimal benefit. Isometric-resistance exercises can be carried out with very little equipment and space and can be performed while patients are bed-bound in hospital or at home. This embedded qualitative study, based in an English hospital trust providing specialist cancer care, was undertaken as a component of a feasibility trial to evaluate the acceptability and feasibility of an isometric-resistance exercise program and explore the suitability of functional assessments by drawing from the experiences of abdominal cancer patients following surgery. Telephone interviews were undertaken with 7 participants in the intervention group, and 8 interviews with the usual care group (n = 15). The gender composition consisted of 11 females and 4 males. Participants' ages ranged from 27 to 84 (M = 60.07, SD = 15.40). Interviews were conducted between August 2017 and May 2018, with audio files digitally recorded and data coded using thematic framework analysis. Our results show that blinding to intervention or usual care was a challenge, participants felt the intervention was safe and suitable aided by the assistance of a research nurse, yet, found the self-completion questionnaire tools hard to complete. Our study provides an insight of trial processes, participants' adherence and completion of exercise interventions, and informs the design and conduct of larger RCTs based on the experiences of abdominal cancer surgery patients.

The use of the CR-10 scale to allow self-regulation of isometric exercise intensity in pre-hypertensive and hypertensive participants.

PURPOSE: Isometric exercise (IE) has been shown to lower blood pressure (BP). Using equipment with force output displays, intensity is usually regulated at 30% maximal voluntary contraction (MVC); however, the cost of programmable equipment and their requirement for maximal contractions presents limitations. A simple, cost-effective alternative deserves investigation. The purpose of this study was (1) to explore the relationship between %MVC, change in systolic BP (ΔSBP), and perceived exertion (CR-10) and (2) to assess the validity of self-regulation of intensity during isometric hand-grip exercise. METHODS: Fourteen pre-hypertensive and hypertensive adults completed eight, 2-min isometric hand-grip exercises at randomised intensities; participants estimated their perceived exertion at 30-s intervals (estimation task). Subsequently, on three separate occasions, participants performed four 2-min contractions at an exertion level that they perceived to be equivalent to CR-10 "Level-6" (production task). RESULTS: There were significant linear relationships between the estimated exertion on the CR-10 scale, and ΔSBP (r = 0.784) and %MVC (r = 0.845). Level-6 was equivalent to an average ΔSBP of 38 mmHg (95% CI; 44, 32 mmHg) and a relative force of 33% MVC (95% CI; 36.2, 30%). During the production task, %MVC was not significantly different between the estimation task and each production trial. In at least the first two repetitions of each production trial, ΔSBP was significantly lower than that observed in the estimation task. CONCLUSION: These findings show that CR-10 "Level-6" is an appropriate method of self-regulating isometric hand-grip intensity; its use offers an affordable and accessible alternative for isometric exercise prescription aimed at reducing BP.

Mechanical power, thrust power and propelling efficiency: relationships with elite sprint swimming performance.

The purpose of this study was to explore the relationships between mechanical power, thrust power, propelling efficiency and sprint performance in elite swimmers. Mechanical power was measured in 12 elite sprint male swimmers: (1) in the laboratory, by using a whole-body swimming ergometer (W'TOT) and (2) in the pool, by measuring full tethered swimming force (FT) and maximal swimming velocity (Vmax): W'T = FT · Vmax. Propelling efficiency (ηP) was estimated based on the "paddle wheel model" at Vmax. Vmax was 2.17 ± 0.06 m · s-1, ηP was 0.39 ± 0.02, W'T was 374 ± 62 W and W'TOT was 941 ± 92 W. Vmax was better related to W'T (useful power output: R = 0.943, P < 0.001) than to W'TOT (total power output: R = 0.744, P < 0.01) and this confirms the use of the full tethered test as a valid test to assess power propulsion in sprinters and to estimate swimming performance. The ratio W'T/W'TOT (0.40 ± 0.04) represents the fraction of total mechanical power that can be utilised in water (e.g., ηP) and was indeed the same as that estimated based on the "paddle wheel model"; this supports the use of this model to estimate ηP in swimming.

Isometric Handgrip as an Adjunct for Blood Pressure Control: a Primer for Clinicians.

Considered a global health crisis by the World Health Organization, hypertension (HTN) is the leading risk factor for death and disability. The majority of treated patients do not attain evidence-based clinical targets, which increases the risk of potentially fatal complications. HTN is the most common chronic condition seen in primary care; thus, implementing therapies that lower and maintain BP to within-target ranges is of tremendous public health importance. Isometric handgrip (IHG) training is a simple intervention endorsed by the American Heart Association as a potential adjuvant BP-lowering treatment. With larger reductions noted in HTN patients, IHG training may be especially beneficial for those who (a) have difficulties continuing or increasing drug-based treatment; (b) are unable to attain BP control despite optimal treatment; (c) have pre-HTN or low-risk stage I mild HTN; and (d) wish to avoid medications or have less pill burden. IHG training is not routinely prescribed in clinical practice. To shift this paradigm, we focus on (1) the challenges of current HTN management strategies; (2) the effect of IHG training; (3) IHG prescription; (4) characterizing the population for whom it works best; (5) clinical relevance; and (6) important next steps to foster broader implementation by clinical practitioners.

Intensity-dependent reductions in resting blood pressure following short-term isometric exercise training.

To reduce resting blood pressure, a minimum isometric exercise training (IET) intensity has been suggested, but this is not known for short-term IET programmes. We therefore compared the effects of moderate- and low-intensity IET programmes on resting blood pressure. Forty normotensive participants (22.3 ± 3.4 years; 69.5 ± 15.5 kg; 170.2 ± 8.7 cm) were randomly assigned to groups of differing training intensities [20%EMGpeak (~23%MVC, maximum voluntary contraction, or 30%EMGpeak (~34%MVC)] or control group; 3 weeks of IET at 30%EMGpeak resulted in significant reductions in resting mean arterial pressure (e.g. -3.9 ± 1.0 mmHg, P < 0.001), whereas 20%EMGpeak did not (-2.3 ± 2.9 mmHg; P > 0.05). Moreover, after pooling all female versus male participants, IET induced a 6.9-mmHg reduction in systolic blood pressure in female participants, but only a 1.5-mmHg reduction in systolic blood pressure in male participants, although the difference was not significant. An IET intensity between 20%EMGpeak and 30%EMGpeak is sufficient to elicit significant resting blood pressure reductions in a short-term training period (3 weeks). In addition, sexual dimorphism may exist in the magnitude of reductions, but further work is required to confirm this possibility, which could be important in understanding the mechanisms responsible.

Isometric Exercise Training and Arterial Hypertension: An Updated Review.

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.

Effects of a 15-week accumulated brisk walking programme on the body composition of primary school children.

The purpose of this study was to establish whether an accumulated brisk walking programme, performed during the school day, is effective in changing body composition in primary school children aged 5-11 years. Altogether, 152 participants (79 boys and 73 girls) took part in this repeated-measures intervention study, divided into groups of walkers and controls. The walkers took part in the intervention during school time, which involved brisk walking around the school grounds for 15 min in the morning and afternoon, at least three times a week for 15 weeks. This represented an additional 90 min of moderate physical activity per week. The controls undertook their usual school day activities. Pre- and post-intervention anthropometric and body composition measures were taken. Body fat (-1.95 ± 2.6%) and fat mass (-0.49 ± 1.0 kg) were significantly reduced in the walkers after the intervention, whereas the controls showed no significant changes in these measures. Our results show that regular accumulated bouts of brisk walking during the school day can positively affect body composition in primary school children.

Commentary: Key Aspects of Multimodal Prehabilitation in Surgical Patients With Cancer. A Practical Approach to Integrating Resistance Exercise Programmes.

Surgical prehabilitation aims to optimise patients' physiological reserves to better withstand the stress of surgery, reduce the risk of postoperative complications, and promote a faster and optimal recovery. The purpose of this commentary is to outline the key aspects of prehabilitation before surgery for cancer which seem to impact its effectiveness and wider implementation. Particular attention is paid to the role and integration of resistance training programmes as a key component of multimodal prehabilitation for patients with cancer. We firstly analyse some of the barriers currently hindering the implementation of prehabilitation programmes in the National Health Service (United Kingdom). Later, we describe essential aspects of resistance training design, such as exercise modality and order execution, volume and intensity, rest periods between sets or exercises, and workout frequency. Furthermore, we propose a methodology to use the perception of effort to control patients' progression during a prehabilitation programme.

Lactate accumulation following isometric exercise training and its relationship with reduced resting blood pressure.

The purpose of this study was (a) to assess lactate accumulation during isometric exercise, and to quantify the shifts in accumulation following isometric training; and (b) to relate any training-induced changes in lactate accumulation to reductions in resting blood pressure. Eleven male participants undertook isometric training for a 4-week period using bilateral-leg exercise. Training caused reductions in systolic, diastolic, and mean arterial resting blood pressure (of -4.9 ± 6.3 mmHg, P = 0.01; -2.6 ± 3.0 mmHg, P = 0.01; and -2.6 ± 2.3 mmHg, P = 0.001 respectively; mean ± s). These were accompanied by changes in muscle activity, taken as electromyographic activity to reach a given lactate concentration (from 114 ± 22 to 131 ± 27 mV and from 136 ± 25 to 155 ± 34 mV for 3 and 4 mmol · L(-1) respectively. Training intensity expressed relative to peak lactate was correlated with reduced resting systolic and mean arterial blood pressure. Training caused significant shifts in lactate accumulation, and reductions in resting blood pressure are strongly related to training intensity, when expressed relative to pre-training peak lactate. This suggests that higher levels of local muscle anaerobiosis may promote the training-induced reductions in resting blood pressure.

A systematic scoping review and textual narrative synthesis of the qualitative evidence related to adolescent idiopathic scoliosis.

INTRODUCTION: This systematic scoping review sought to summarise and synthesise the qualitative evidence on adolescent idiopathic scoliosis (AIS) to understand the experiences of AIS, and of its diagnosis and treatment, and effective coping strategies to inform directions for future research. METHOD: A systematic scoping review and textual narrative synthesis was undertaken. Qualitative or mixed-methods studies with extractable qualitative data were included if participants had AIS, and patient or patient relative perspectives about AIS or its treatment were reported. RESULTS: Fifteen papers were included. These suggested that AIS can influence self-image and perceptions of appearance and can cause those with the condition to reluctantly adjust parts of their lives and avoid some activities. The diagnosis and treatment of AIS is a major event and is often accompanied by shock, uncertainty, and anxiety. Whilst some find surgery stressful, others were relieved to have the surgery, and were generally happy with the outcome. Immediate family members may be distressed by the diagnosis and treatment of AIS. DISCUSSION: AIS diagnosis and treatment has a substantial impact on adolescents and their families that is only addressed in part in this review. There is a pressing need for more qualitative research to understand needs, perspectives and experiences of adolescents with AIS and their families from the point of diagnosis, throughout treatment, and in the longer-term.

Effects of isometric leg training on ambulatory blood pressure and morning blood pressure surge in young normotensive men and women.

Despite the reported association between diurnal variations in ambulatory blood pressure (BP) and elevated cardiovascular disease risk, little is known regarding the effects of isometric resistance training (IRT), a practical BP-lowering intervention, on ambulatory BP and morning BP surge (MBPS). Thus, we investigated whether (i) IRT causes reductions in ambulatory BP and MBPS, in young normotensives, and (ii) if there are any sex differences in these changes. Twenty normotensive individuals (mean 24-h SBP = 121 ± 7, DBP = 67 ± 6 mmHg) undertook 10-weeks of bilateral-leg IRT (4 × 2-min/2-min rest, at 20% maximum voluntary contraction (MVC) 3 days/week). Ambulatory BP and MBPS (mean systolic BP (SBP) 2 h after waking minus the lowest sleeping 1 h mean SBP) was measures pre- and post-training. There were significant reductions in 24-h ambulatory SBP in men (- 4 ± 2 mmHg, P = 0.0001) and women (- 4 ± 2 mmHg, P = 0.0001) following IRT. Significant reductions were also observed in MBPS (- 6 ± 8 mmHg, p = 0.044; - 6 ± 7 mmHg, P = 0.019), yet there were no significant differences between men and women in these changes, and 24-h ambulatory diastolic BP remained unchanged. Furthermore, a significant correlation was identified between the magnitude of the change in MBPS and the magnitude of changes in the mean 2-h SBP after waking for both men and women (men, r = 0.89, P = 0.001; women, r = 0.74, P = 0.014). These findings add further support to the idea that IRT, as practical lifestyle intervention, is effective in significantly lowering ambulatory SBP and MBPS and might reduce the incidence of adverse cardiovascular events that often occur in the morning.

Getting the best GRIP on blood pressure control: Investigating a cost-effective isometric handgrip alternative.

OBJECTIVES: The World Health Organization emphasises the need for cost-effective alternative methods to lower blood pressure (BP). Endorsed nationally in HTN guidelines, isometric handgrip (IHG) training is an alternative method of BP control. The purpose of this study was to compare the BP, heart rate (HR) and rates of perceived exertion (RPE) responses between a bout of IHG training performed using the traditional computerized device and a more affordable, inflatable stress ball. METHODS: Twenty healthy adults performed one bout (4, 2-min isometric contractions, with 1-min rests between each contraction at 30% maximal voluntary contraction) of IHG training using the traditional computerized device, and one bout with the inflatable stress ball. BP, HR, and RPE were recorded. RESULTS: No statistically significant differences between devices were observed with HR, BP, and RPE (p < 0.05). However, average RPE for both devices ranged between 5 and 6 indicating that participants were rating 30% of their MVC, consistent with previous work. DISCUSSION: The similar cardiovascular and psychophysical responses provide support for the potential use of this low individual- and provider-burden, cost-efficient IHG device, and lay the foundation for a future training study to test the hypothesis of benefit.

Developing an Evidence and Theory Based Multimodal Integrative Intervention for the Management of Renal Cachexia: A Theory of Change.

In this study, we aimed to develop a theoretical framework for a multimodal, integrative, exercise, anti-inflammatory and dietary counselling (MMIEAD) intervention for patients with renal cachexia with reference to how this addresses the underlying causal pathways for renal cachexia, the outcomes anticipated, and how these will be evaluated. We used a Theory of Change (ToC) approach to guide six steps. Step 1 included inputs from a workshop to obtain key stakeholder views on the potential development of a multimodal intervention for renal cachexia. Step 2 included the findings of a mixed-methods study with Health Care Practitioners (HCPs) caring for individuals with End Stage Kidney Disease (ESKD) and cachexia. Step 3 included the results from our systematic literature review on multimodal interventions for cachexia management. In step 4, we used the body of our research team's cachexia research and wider relevant research to gather evidence on the specific components of the multimodal intervention with reference to how this addresses the underlying causal pathways for renal cachexia. In steps 5 and 6 we developed and refined the ToC map in consultation with the core research team and key stakeholders which illustrates how the intervention components of MMIEAD interact to achieve the intended long-term outcomes and anticipated impact. The results of this study provide a theoretical framework for the forthcoming MMIEAD intervention for those with renal cachexia and in subsequent phases will be used to determine whether this intervention is effective. To the best of our knowledge no other multimodal intervention trials for cachexia management have reported a ToC. Therefore, this research may provide a useful framework and contribute to the ongoing development of interventions for cachexia management.

Exploring the lived experience of renal cachexia for individuals with end-stage renal disease and the interrelated experience of their carers: Study protocol.

Renal cachexia is an important consideration in the person-centred care that is needed in end-stage renal disease (ESRD). However, given that clinical guidelines relating to renal cachexia are largely absent, this is an unmet care need. To inform guidelines and future renal service planning, there is an urgency to understand individuals' experiences of renal cachexia and the interrelated experiences of the carers in their lives. We report here the protocol for an interpretative phenomenological study which will explore this lived experience. A purposive sampling strategy will recruit individuals living with ESRD who have cachexia and their carers. A maximum of 30 participants (15 per group) dependent on saturation will be recruited across two nephrology directorates, within two healthcare trusts in the United Kingdom. Individuals with renal cachexia undergoing haemodialysis will be recruited via clinical gatekeepers and their carers will subsequently be invited to participate in the study. Participants will be offered the opportunity to have a face-to-face, virtual or telephone interview. Interviews will be audio-recorded, transcribed verbatim and analysed using interpretative phenomenological analysis. NVivo, will be used for data management. Ethical approval for this study was granted by the Office for Research Ethics Committees Northern Ireland (REC Reference: 22/NI/0107). Scientific evidence tends to focus on measurable psychological, social and quality of life outcomes but there is limited research providing in-depth meaning and understanding of the views of individuals with renal disease who are experiencing renal cachexia. This information is urgently needed to better prepare healthcare providers and in turn support individuals with ESRD and their carers. This study will help healthcare providers understand what challenges individuals with ESRD, and their carers face in relation to cachexia and aims to inform future clinical practice guidelines and develop supportive interventions which recognise and respond to the needs of this population.

Chin tuck against resistance exercise with feedback to improve swallowing, eating and drinking in frail older people admitted to hospital with pneumonia: protocol for a feasibility randomised controlled study.

BACKGROUND: Swallowing difficulties (dysphagia) and community-acquired pneumonia are common in frail older people and maybe addressed through targeted training of the anterior neck musculature that affects the swallow. We have developed a swallowing exercise rehabilitation intervention (CTAR-SwiFt) by adapting a previously established swallowing exercise to ensure patient safety and ease of execution in the frail elderly population. The CTAR-SwiFt intervention consists of a feedback-enabled exercise ball that can be squeezed under the chin, with real-time feedback provided via a mobile application. The aim of this study is to evaluate the feasibility of assessing the effectiveness of the CTAR-SwiFt intervention in reducing dysphagia and community-acquired pneumonia, prior to a larger-scale multi-centre randomised controlled trial. METHODS: We will recruit 60 medically stable patients over the age of 75 years who have been admitted with a diagnosis of pneumonia to the acute frailty wards at two participating hospitals in the UK. Study participants will be randomised into one of three groups: standard care, low intensity (once daily) CTAR-SwiFt exercise or high intensity (twice daily) CTAR-SwiFt exercises. The intervention period will last for 12 weeks, the final follow-up assessment will be conducted at 24 weeks. We will assess the feasibility outcomes, including rates of participant recruitment and retention, compliance with the exercise regime and adverse incidents. Additionally, we will assess the usability and acceptability of the intervention device and the performance of different clinical outcome measures (e.g. chin tuck strength, Functional Oral Intake Scale, SWAL-QOL, EQ-5D and swallow speed). A sub-sample of study participants will complete videofluoroscopic assessments of swallowing function before and after the intervention to evaluate the physiological changes (e.g. bolus flow rates, laryngeal elevation, base-of-tongue retraction). CONCLUSIONS: By improving the ability to swallow, using our chin tuck exercise intervention, in frail older patients admitted to hospital with pneumonia, it is anticipated that patients' oral intake will improve. It is suggested that this will further impact clinical, patient and healthcare economic outcomes, i.e. reduce the need for supplemental feeding, improve patient satisfaction with oral intake and swallowing-related quality of life, decrease the occurrence of chest infections and reduce hospital admissions and related healthcare costs. TRIAL REGISTRATION: ISRCTN, ISRCTN12813363 . Registered on 20 January 2020.

Markers of isometric training intensity and reductions in resting blood pressure.

In this study, we examined the correlations between selected markers of isometric training intensity and subsequent reductions in resting blood pressure. Thirteen participants performed a discontinuous incremental isometric exercise test to volitional exhaustion at which point mean torque for the final 2-min stage (2min-torque(peak)) and peak heart rate peak (HR(peak)) were identified. Also, during 4 weeks of training (3 sessions per week, comprising 4 × 2 min bilateral leg isometric exercise at 95% HR(peak)), heart rate (HR(train)), torque (Torque(train)), and changes in EMG amplitude (ΔEMG(amp)) and frequency (ΔEMG(freq)) were determined. The markers of training intensity were: Torque(train) relative to the 2min-torque(peak) (%2min-torque(peak)), EMG relative to EMG(peak) (%EMG(peak)), HR(train) ΔEMG(amp), ΔEMG(freq), and %MVC. Mean systolic (-4.9 mmHg) and arterial blood pressure (-2.7mmHg) reductions correlated with %2min-torque(peak) (r = -0.65, P = 0.02 and r = -0.59, P = 0.03), ΔEMG(amp) (r = 0.66, P = 0.01 and r = 0.59, P = 0.03), ΔEMG(freq) (r = -0.67, P = 0.01 and r = -0.64, P = 0.02), and %EMG(peak) (systolic blood pressure only; r = -0.63, P = 0.02). These markers best reflect the association between isometric training intensity and reduction in resting blood pressure observed after bilateral leg isometric exercise training.

Blood pressure-lowering efficacy of a 6-week multi-modal isometric exercise intervention.

Isometric exercise training (IET) is an effective method for reducing resting blood pressure (BP). To date, no research studies have been conducted using multiple exercises within an IET intervention. Previous research has suggested that varied exercise programmes may have a positive effect on adherence. Therefore, this randomized controlled study aimed to investigate the BP-lowering efficacy of a multi-modal IET (MIET) intervention in healthy young adults. Twenty healthy participants were randomized to an MIET [n = 10; four women; SBP 117.9 ± 6.9 mmHg; DBP 66.3 ± 5.1 mmHg] or control (CON) group (n = 10; five women; SBP, 123.3 ± 10.4 mmHg; DBP, 77.3 ± 6.7 mmHg). The MIET group completed three sessions per week of 4, 2-min isometric contractions, with a 1-min rest between each contraction, for 6 weeks. Resting BP and heart rate (HR) were measured at baseline and post-intervention. Pre-to-post intervention within-group reductions in resting BP were observed (SBP: 5.3 ± 6.1 mmHg, DBP: 3.4 ± 3.7 mmHg, MAP: 4.0 ± 3.9 mmHg, HR: 4.8 ±6 .6 bpm), although clinically relevant (≥2 mmHg), these changes were not statistically significant. Significant (p < 0.05) between-group differences were found between the intervention and control groups, indicating that the MIET intervention has a greater BP-lowering effect compared to control. The clinically relevant post-training reductions in resting BP suggest that MIET may be a promising additional IET method for hypertension prevention. These findings; however, must be interpreted with caution due to the small sample size and the non-clinical cohort.

The effects of performing isometric training at two exercise intensities in healthy young males.

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 x 2 min exercise bouts 3x 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.

Reductions in resting blood pressure after 4 weeks of isometric exercise training.

There is some evidence to suggest isometric training can reduce resting blood pressure in a shorter period than the typical 8 weeks, reported most commonly. The purpose of the present study was to explore whether 4 weeks of bilateral-leg isometric training can reduce resting blood pressure, and whether these changes are associated with altered cardiac output or total peripheral resistance. Thirteen participants volunteered for a 4-week crossover training study, involving three sessions per week (each session involving 4 x 2 min bilateral-leg isometric exercise). The training intensity used (95% peak HR) was equivalent to 24% MVC. In addition to blood pressure, resting heart rate, cardiac output, stroke volume, and total peripheral resistance were measured. Results demonstrated that bilateral-leg isometric exercise training for 4 weeks caused significant reductions in systolic, diastolic, and mean arterial pressure. Changes were -4.9 +/- 5.8, -2.8 +/- 3.2, and -2.7 +/- 2.4 mmHg, respectively. No differences were observed in the other resting measures. In conclusion, this study has shown that it is possible to induce reductions in arterial blood pressure after 4 weeks of bilateral-leg isometric exercise.