Equipment-free, unsupervised high intensity interval training elicits significant improvements in the physiological resilience of older adults

Background

Reduced cardiorespiratory fitness (CRF) is an independent risk factor for dependency, cognitive impairment and premature mortality. High-intensity interval training (HIIT) is a proven time-efficient stimulus for improving both CRF and other facets of cardiometabolic health also known to decline with advancing age. However, the efficacy of equipment-free, unsupervised HIIT to improve the physiological resilience of older adults is not known.

Methods

Thirty independent, community-dwelling older adults (71(SD: 5) years) were randomised to 4 weeks (12 sessions) equipment-free, supervised (in the laboratory (L-HIIT)) or unsupervised (at home (H-HIIT)) HIIT, or a no-intervention control (CON). HIIT involved 5, 1-minute intervals of a bodyweight exercise each interspersed with 90-seconds recovery. CRF, exercise tolerance, blood pressure (BP), body composition, muscle architecture, circulating lipids and glucose tolerance were assessed at baseline and after the intervention period.

Results

When compared to the control group, both HIIT protocols improved the primary outcome of CRF ((via anaerobic threshold) mean difference, L-HIIT: +2.27, H-HIIT: +2.29, both p < 0.01) in addition to exercise tolerance, systolic BP, total cholesterol, non-HDL cholesterol and m. vastus lateralis pennation angle, to the same extent. There was no improvement in these parameters in CON. There was no change in diastolic BP, glucose tolerance, whole-body composition or HDL cholesterol in any of the groups.

Conclusions

This is the first study to show that short-term, time-efficient, equipment-free, HIIT is able to elicit improvements in the CRF of older adults irrespective of supervision status. Unsupervised HIIT may offer a novel approach to improve the physiological resilience of older adults, combating age-associated physiological decline, the rise of inactivity and the additional challenges currently posed by the COVID-19 pandemic.

Trial registration

This study was registered at clinicaltrials.gov and coded: NCT03473990.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03208-y.

Curcumin Enhances Fed-State Muscle Microvascular Perfusion but Not Leg Glucose Uptake in Older Adults

Therapeutic interventions aimed at enhancing blood flow may combat the postprandial vascular and metabolic dysfunction that manifests with chronological ageing. We compared the effects of acute curcumin (1000 mg) coupled with an oral nutritional supplement (ONS, 7.5 g protein, 24 g carbohydrate and 6 g fat) versus a placebo and ONS (control) on cerebral and leg macrovascular blood flow, leg muscle microvascular blood flow, brachial artery endothelial function, and leg insulin and glucose responses in healthy older adults (n = 12, 50% male, 73 ± 1 year). Curcumin enhanced m. tibialis anterior microvascular blood volume (MBV) at 180 and 240 min following the ONS (baseline: 1.0 vs. 180 min: 1.08 ± 0.02, p = 0.01 vs. 240 min: 1.08 ± 0.03, p = 0.01), and MBV was significantly higher compared with the control at both time points (p < 0.05). MBV increased from baseline in the m. vastus lateralis at 240 min after the ONS in both groups (p < 0.05), and there were no significant differences between groups. Following the ONS, leg blood flow and leg vascular conductance increased, and leg vascular resistance decreased similarly in both conditions (p < 0.05). Brachial artery flow-mediated dilation and middle cerebral artery blood flow were unchanged in both conditions (p > 0.05). Similarly, the curcumin and control groups demonstrated comparable increases in glucose uptake and insulin in response to the ONS. Thus, acute curcumin supplementation enhanced ONS-induced increases in m. tibialis anterior MBV without potentiating m. vastus lateralis MBV, muscle glucose uptake, or systemic endothelial or macrovascular function in healthy older adults.

Green Tea Extract Concurrent with an Oral Nutritional Supplement Acutely Enhances Muscle Microvascular Blood Flow without Altering Leg Glucose Uptake in Healthy Older Adults

Postprandial macro- and microvascular blood flow and metabolic dysfunction manifest with advancing age, so vascular transmuting interventions are desirable. In this randomised, single-blind, placebo-controlled, crossover trial, we investigated the impact of the acute administration of green tea extract (GTE; containing ~500 mg epigallocatechin-3-gallate) versus placebo (CON), alongside an oral nutritional supplement (ONS), on muscle macro- and microvascular, cerebral macrovascular (via ultrasound) and leg glucose/insulin metabolic responses (via arterialised/venous blood samples) in twelve healthy older adults (42% male, 74 ± 1 y). GTE increased m. vastus lateralis microvascular blood volume (MBV) at 180 and 240 min after ONS (baseline: 1.0 vs. 180 min: 1.11 ± 0.02 vs. 240 min: 1.08 ± 0.04, both p < 0.005), with MBV significantly higher than CON at 180 min (p < 0.05). Neither the ONS nor the GTE impacted m. tibialis anterior perfusion (p > 0.05). Leg blood flow and vascular conductance increased, and vascular resistance decreased similarly in both conditions (p < 0.05). Small non-significant increases in brachial artery flow-mediated dilation were observed in the GTE only and middle cerebral artery blood flow did not change in response to GTE or CON (p > 0.05). Glucose uptake increased with the GTE only (0 min: 0.03 ± 0.01 vs. 35 min: 0.11 ± 0.02 mmol/min/leg, p = 0.007); however, glucose area under the curve and insulin kinetics were similar between conditions (p > 0.05). Acute GTE supplementation enhances MBV beyond the effects of an oral mixed meal, but this improved perfusion does not translate to increased leg muscle glucose uptake in healthy older adults.

Short-Term, Equipment-Free High Intensity Interval Training Elicits Significant Improvements in Cardiorespiratory Fitness Irrespective of Supervision in Early Adulthood

Introduction: Serious health implications from having low levels of cardiorespiratory fitness (CRF) and being overweight in young adulthood are carried forward into later life. High-intensity interval training (HIIT) is a time-effective, potent stimulus for improving CRF and indices of cardiometabolic health. To date, few studies have investigated the use of equipment-free HIIT or the impact of supervision for improving CRF via HIIT. Methods: Thirty healthy young adults (18-30 y) were randomised to 4 weeks (12 sessions) equipment-free, bodyweight based supervised laboratory HIIT (L-HIIT), unsupervised home HIIT (H-HIIT) or no-intervention (CON). Utilised exercises were star jumps, squats and standing sprints. Measurements of CRF (anaerobic threshold (AT) and VO₂peak), blood pressure (BP), body mass index (BMI), blood glucose and plasma insulin by oral glucose tolerance test (OGTT), and muscle architecture were performed at baseline and after the intervention. Results: When compared to the control group, both HIIT protocols improved CRF (AT: L-HIIT mean difference compared to the control group (MD) +2.1 (95% CI: 0.34-4.03) ml/kg/min; p = 0.02; H-HIIT MD +3.01 (1.17-4.85) ml/kg/min; p = 0.002), VO₂peak: L-HIIT (MD +2.94 (0.64-5.25) ml/kg/min; p = 0.01; H-HIIT MD +2.55 (0.34-4.76) ml/kg/min; p = 0.03), BMI (L-HIIT MD -0.43 (-0.86 to 0.00) kg/m²; p = 0.05; H-HIIT: MD -0.51 (-0.95 to -0.07) kg/m²; p = 0.03) and m. vastus lateralis pennation angle (L-HIIT MD 0.2 (0.13-0.27)°; p < 0.001; H-HIIT MD 0.17 (0.09 to 0.24)°; p < 0.001). There was no significant change in BP, blood glucose or plasma insulin in any of the groups. Conclusions: Four weeks time-efficient, equipment-free, bodyweight-based HIIT is able to elicit improvements in CRF irrespective of supervision status. Unsupervised HIIT may be a useful tool for counteracting the rise of sedentary behaviours and consequent cardiometabolic disorders in young adults.

Cocoa Flavanols Adjuvant to an Oral Nutritional Supplement Acutely Enhances Nutritive Flow in Skeletal Muscle without Altering Leg Glucose Uptake Kinetics in Older Adults

Ageing is associated with postprandial muscle vascular and metabolic dysfunction, suggesting vascular modifying interventions may be of benefit. Reflecting this, we investigated the impact of acute cocoa flavanol (450-500 mg) intake (versus placebo control) on vascular (via ultrasound) and glucose/insulin metabolic responses (via arterialised/venous blood samples and ELISA) to an oral nutritional supplement (ONS) in twelve healthy older adults (50% male, 72 ± 4 years), in a crossover design study. The cocoa condition displayed significant increases in m. vastus lateralis microvascular blood volume (MBV) in response to feeding at 180 and 240-min after ONS consumption (baseline: 1.00 vs. 180 min: 1.09 ± 0.03, p = 0.05; 240 min: 1.13 ± 0.04, p = 0.002), with MBV at these timepoints significantly higher than in the control condition (p < 0.05). In addition, there was a trend (p = 0.058) for MBV in m. tibialis anterior to increase in response to ONS in the cocoa condition only. Leg blood flow and vascular conductance increased, and vascular resistance decreased in response to ONS (p < 0.05), but these responses were not different between conditions (p > 0.05). Similarly, glucose uptake and insulin increased in response to ONS (p < 0.05) comparably between conditions (p > 0.05). Thus, acute cocoa flavanol supplementation can potentiate oral feeding-induced increases in MBV in older adults, but this improvement does not relay to muscle glucose uptake.

Fasting and surgery timing (FaST) audit

BACKGROUND & AIMS

International guidance advocates the avoidance of prolonged preoperative fasting due to its negative impact on perioperative hydration. This study aimed to assess the adherence to these guidelines for fasting in patients undergoing elective and emergency surgery in the East Midlands region of the UK.

METHODS

This prospective audit was performed over a two-month period at five National Health Service (NHS) Trusts across the East Midlands region of the UK. Demographic data, admission and operative details, and length of preoperative fasting were collected on adult patients listed for emergency and elective surgery.

RESULTS

Of the 343 surgical patients included within the study, 50% (n = 172) were male, 78% (n = 266) had elective surgery and 22% (n = 77) underwent emergency surgery. Overall median fasting times (Q1, Q3) were 16.1 (13.0, 19.4) hours for food and 5.8 (3.5, 10.7) hours for clear fluids. Prolonged fasting >12 h was documented in 73% (n = 250) for food, and 21% (n = 71) for clear fluids. Median fasting times from clear fluids and food were longer in the those undergoing emergency surgery when compared with those undergoing elective surgery: 13.0 (6.4, 22.6) vs. 4.9 (3.3, 7.8) hours, and 22.0 (14.0, 37.4) vs. 15.6 (12.9, 17.8) hours respectively, p < 0.0001.

CONCLUSIONS

Despite international consensus on the duration of preoperative fasting, patients continue to fast from clear fluids and food for prolonged lengths of time. Patients admitted for emergency surgery were more likely to fast for longer than those having elective surgery.

Winter cancellations of elective surgical procedures in the UK: a questionnaire survey of patients on the economic and psychological impact

OBJECTIVES

To quantify the economic and psychological impact of the cancellation of operations due to winter pressures on patients, their families and the economy.

DESIGN

This questionnaire study was designed with the help of patient groups. Data were collected on the economic and financial burden of cancellations. Emotions were also quantified on a 5-point Likert scale.

SETTING

Five NHS Hospital Trusts in the East Midlands region of England.

PARTICIPANTS

We identified 796 participants who had their elective operations cancelled between 1 November 2017 and 31 March 2018 and received responses from 339 (43%) participants.

INTERVENTIONS

Participants were posted a modified version of a validated quality of life questionnaire with a prepaid return envelope.

MAIN OUTCOME MEASURES

The primary outcome measures were the financial and psychological impact of the cancellation of elective surgery on patients and their families.

RESULTS

Of the 339 respondents, 163 (48%) were aged <65 years, with 111 (68%) being in employment. Sixty-six (19%) participants had their operations cancelled on the day. Only 69 (62%) of working adults were able to return to work during the time scheduled for their operation, with a mean loss of 5 working days (SD 10). Additional working days were lost subsequently by 60 (54%) participants (mean 7 days (SD 10)). Family members of 111 (33%) participants required additional time off work (mean 5 days (SD 7)). Over 30% of participants reported extreme levels of sadness, disappointment, anger, frustration and stress. At least moderate concern about continued symptoms was reported by 234 (70%) participants, and 193 (59%) participants reported at least moderate concern about their deteriorating condition.

CONCLUSIONS

The cancellation of elective surgery during the winter had an adverse impact on patients and the economy, including days of work lost and health-related anxiety. We recommend better planning, and provision of more notice and better support to patients.