Light-intensity Walking Research Articles

Combining Structured Exercise with Interrupting Sitting Elicits Superior Cardiovascular Benefits Than Either Strategy Alone.

This study aimed to determine whether interrupting prolonged sitting with brief bouts of light-intensity activity (ISIT), undertaking structured high-intensity interval training (HIIT), or the combination of both interventions would elicit greater cardiometabolic benefits. Seventeen healthy adults (22-50 years) were recruited to undertake three 2-week interventions in a random order: i) HIIT (6 HIIT sessions + <5000 steps following the session and on the next day), ii) ISIT (2.5 min light-intensity walking every hour for 12 h/day on weekdays), and iii) HIIT+ISIT. Participants underwent a 6-day lead-in phase prior to each condition (day 1-3: normal activity, day 4-6 sedentary: <5000 steps/day). Pre and post assessments included glycemic control (primary outcome 2-h postprandial glucose), endothelial function via flow-mediated dilation (FMD), cardiorespiratory fitness and body composition. Changes in primary and secondary outcomes were assessed via repeated measures ANOVA. Eleven participants completed all conditions (8 Female, 33±5 years, 23±4 kg/m2, habitual activity 7,156±2,272 steps/day). FMD significantly improved following HIIT+ISIT when compared to ISIT (+1.04±1.20%, p=0.02), but there were no differences when ISIT was directly compared to HIIT. Cardiorespiratory fitness improved significantly following HIIT+ISIT when compared to ISIT (+1.88±2.03 mL/kg/min, p=0.01) but there were no differences when ISIT alone was compared to HIIT. There were no significant differences between groups for outcomes related to glucose control or body composition. HIIT+ISIT elicits greater improvements in cardiovascular outcomes when compared to ISIT but not HIIT. The benefits of structured exercise, such as HIIT, may go beyond those achieved by limiting sedentary behavior alone.

Light Walking Patterns and Postprandial Cardiometabolic Responses in Young Obese Adults: A Randomized Crossover Study.

Recent studies suggest that light-intensity physical activity may enhance cardiometabolic health and reduce mortality risk in adults. However, more information is required to understand the patterns of light-intensity physical activity and postprandial cardiometabolic health. This study examined the effects of different light-intensity walking patterns on postprandial cardiometabolic responses in young obese adults. A randomized crossover trial was conducted. The study was conducted in the laboratory. The study analyzed baseline (fasting) and 6-hour postprandial concentrations of glucose, insulin, triglycerides, and blood pressure (BP) in 16 young obese adults. Participants underwent four 7-hour experimental conditions with a 7-20-day washout period: uninterrupted sitting (SIT), 30-minute light-intensity walking (EX+SIT), 3-minute light-intensity walking every 30 minutes (BR), and 30-minute light-intensity walking with 3-minute light-intensity walking every 30 minutes (EX+BR). Incremental areas under the curve (iAUC) for each outcome and average BP were compared between SIT and walking conditions. Compared with SIT, all walking conditions reduced iAUCs for glucose and average diastolic BP (all p<0.05). Only EX+SIT and EX+BR reduced iAUCs for insulin (p<0.05). No significant differences were found for triglycerides iAUC and systolic BP between the four conditions (all p>0.05). All patterns of light-intensity walking reduced postprandial glucose concentrations and diastolic BP in young obese adults, suggesting benefits for glycemic control. Continuous 30-minute light-intensity walking alone, or combined with brief 3-min bouts also attenuated postprandial insulin concentrations, highlighting light-intensity walking as a promising strategy for improving cardiometabolic health in young obese adults.

Acute effects of breaking up sitting time with isometric exercise on cognition in healthy adults

The aim of this study was to analyze the acute effects of different sitting break strategies on cognition in healthy adults. Twelve physically inactive adults (8 women, 28 ± 9 years; 25.10 ± 4.90 kg/m²) randomly completed three 3 hour conditions: 2-min isometric leg extension exercise sitting breaks at 30% of maximal voluntary contraction every 30-min; 2-min light-intensity walking sitting breaks every 30-min; sitting without breaks. Stroop and Eriksen Flanker tests were used to measure cognition before and after conditions. Generalized estimated equations were used to analyze cognition responses. Data are presented as mean ± standard deviation. Stroop congruent phase decreased for all conditions (Isometric: 1.56 ± 0.20s Pre vs 1.49 ± 0.12s Post; Walking: 1.67 ± 0.22s Pre vs 1.54 ± 0.19s Post; Control: 1.69 ± 0.24s Pre vs 1.59 ± 0.26s Post; p = 0.044). There were no significant effects on Stroop incongruent phase, Stroop effect, or Eriksen-Flanker (p &gt; 0.05 for all). In conclusion, walking or isometric exercise sitting breaks do not acutely improve cognition in healthy adults.

Effects of Interrupting Prolonged Sitting with Light-Intensity Physical Activity on Inflammatory and Cardiometabolic Risk Markers in Young Adults with Overweight and Obesity: Secondary Outcome Analyses of the SED-ACT Randomized Controlled Crossover Trial.

Sedentary behavior (SB) is an essential risk factor for obesity, cardiovascular disease, and type 2 diabetes. Though certain levels of physical activity (PA) may attenuate the detrimental effects of SB, the inflammatory and cardiometabolic responses involved are still not fully understood. The focus of this secondary outcome analysis was to describe how light-intensity PA snacks (LIPASs, alternate sitting and standing, walking or standing continuously) compared with uninterrupted prolonged sitting affect inflammatory and cardiometabolic risk markers. Seventeen young adults with overweight and obesity participated in this study (eight females, 23.4 ± 3.3 years, body mass index (BMI) 29.7 ± 3.8 kg/m2, glycated hemoglobin A1C (HbA1c) 5.4 ± 0.3%, body fat 31.8 ± 8.2%). Participants were randomly assigned to the following conditions which were tested during an 8 h simulated workday: uninterrupted prolonged sitting (SIT), alternate sitting and standing (SIT-STAND, 2.5 h total standing time), continuous standing (STAND), and continuous walking (1.6 km/h; WALK). Each condition also included a standardized non-relativized breakfast and lunch. Venous blood samples were obtained in a fasted state at baseline (T0), 1 h after lunch (T1) and 8 h after baseline (T2). Inflammatory and cardiometabolic risk markers included interleukin-6 (IL-6), c-reactive protein (CRP), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TGs), visceral fat area (VFA), triglyceride-glucose (TyG) index, two lipid ratio measures, TG/HDL-C and TC/HDL-C, albumin, amylase (pancreatic), total protein, uric acid, and urea. We found significant changes in a broad range of certain inflammatory and cardiometabolic risk markers during the intervention phase for IL-6 (p = 0.014), TG (p = 0.012), TC (p = 0.017), HDL-C (p = 0.020), LDL-C (p = 0.021), albumin (p = 0.003), total protein (p = 0.021), and uric acid (p = 0.040) in favor of light-intensity walking compared with uninterrupted prolonged sitting, alternate sitting and standing, and continuous standing. We found no significant changes in CRP (p = 0.529), creatinine (p = 0.199), TyG (p = 0.331), and the lipid ratios TG/HDL-C (p = 0.793) and TC/HDL-C (p = 0.221) in response to the PA snack. During a simulated 8 h work environment replacement and interruption of prolonged sitting with light-intensity walking, significant positive effects on certain inflammatory and cardiometabolic risk markers were found in young adults with overweight and obesity.

Effects of light-intensity physical activity on cardiometabolic parameters in young adults with overweight and obesity: The SED-ACT randomized controlled crossover trial.

To investigate how a change in body position with light-intensity physical activity (PA) 'snacks' (LIPAS, alternate sitting and standing, walking or standing continuously) compared with uninterrupted prolonged sitting affects glucose metabolism and heart rate variability (HRV) parameters in young adults with overweight and obesity. We conducted a four-arm randomized controlled crossover trial. The following conditions were tested during an 8-h simulated workday: uninterrupted prolonged sitting (SIT), alternate sitting and standing (SIT-STAND; 2.5 h total), continuous standing (STAND), and continuous walking (1.0 mph; WALK). The primary outcome was to investigate how a change in body position (alternate sitting and standing, walking or standing continuously) compared with uninterrupted sitting affects mean 8-h glucose metabolism. Secondary outcomes included the effects on 2-h postprandial glucose concentrations, as well as on 8-h/24-h heart rate and HRV parameters, in the respective study arms. Capillary blood samples were drawn from an hyperemised earlobe in the fasted state and once every hour during each trial intervention by puncturing the earlobe with a lancet and collecting 20 μL of blood (Biosen S-Line Lab+; EKF diagnostics, Barleben, Germany). HRV was assessed for 24 h including the 8-h intervention phase, and a home phase by means of a Holter electrocardiogram. All participants received the same standardized non-relativised breakfast and lunch during the four trial visits. Seventeen individuals (eight women, mean age 23.4 ± 3.3 years, body mass index 29.7 ± 3.8 kg/m2, glycated haemoglobin level 34.8 ± 3.1 mmol/mol [5.4 ± 0.3%], body fat 31.8 ± 8.2%) completed all four trial arms. Compared with SIT (89.4 ± 6.8 mg/dL), 8-h mean glucose was lower in all other conditions (p < 0.05) and this was statistically significant compared with WALK (86.3 ± 5.2 mg/dL; p = 0.034). Two-hour postprandial glucose after breakfast was approximately 7% lower for WALK compared with SIT (p = 0.002). Furthermore, significant time × condition effects on HRV parameters favouring light-intensity walking were observed (p < 0.001). Replacement and interruption of prolonged sitting with light-intensity walking showed a significant blood glucose-lowering effect and improved HRV during an 8-h work environment in young adults with overweight and obesity.

Effects of neuromuscular electrical stimulation, light intensity walking and a seated exercise trainer on venous return in healthy young adults: a quasi-experimental crossover study

Background/Aims The growing prevalence of sedentary behaviour across the life course is linked to an increased risk of chronic venous disease and related mortality, warranting the need for non-invasive interventions to improve blood flow and lower extremity function. The aim of this study was to investigate the change in venous blood flow, heart rate and blood pressure after 8 minutes of using the Leeper device, Circulation Booster and light intensity walking. Methods A quasi-experimental crossover study involving 11 participants (eight women, three men, mean age 23.91 years, standard deviation 1.04 years) was conducted using Leeper and Circulation Booster devices and light intensity walking. During each intervention, participants exercised for 8 minutes, and blood flow was recorded at 0, 4 and 8 minutes. Heart rate and blood pressure were recorded at 0 and 8 minutes. Blood flow was the primary outcome measure, and heart rate and blood pressure were secondary outcomes. Participants rested for 10 minutes between exercise. A two-way repeated measures analysis of variance was used to analyse the effect of intervention and time on blood flow, blood pressure and heart rate. Results There was no significant interaction between intervention and time on blood flow (P=0.180) indicating that blood flow did not change over time depending on intervention. There was no significant main effect of time on blood flow (P=0.206), indicating that no intervention caused a significant increase or decrease in blood flow after 8 minutes of exercise. Conclusions The interventions involving the Leeper and Circulation Booster devices and light intensity walking did not appear to significantly increase blood flow in young adults. Further studies involving participants from older age groups and those with pathological interventions are warranted to examine the potential effectiveness of these interventions. Implications for practice The findings may assist with the advice that allied health professionals provide regarding the use of seated exercise trainers and EMS devices and their ability to influence changes in blood flow.

Effects of neuromuscular electrical stimulation, light intensity walking and a seated exercise trainer on venous return in healthy young adults: a quasi-experimental crossover study

Effects of neuromuscular electrical stimulation, light intensity walking and a seated exercise trainer on venous return in healthy young adults: a quasi-experimental crossover study

Short, frequent, light-intensity walking activity improves postprandial vascular-inflammatory biomarkers in people with type 1 diabetes: The SIT-LESS randomized controlled trial.

To examine the effect of interrupting prolonged sitting with short, frequent, light-intensity activity on postprandial cardiovascular markers in people with type 1 diabetes (T1D). In a randomized crossover trial, 32 adults with T1D (mean ± SD age 28 ± 5 years, glycated haemoglobin 67.9 ± 12.6 mmol/mol, 17 women) completed two 7-h laboratory visits separated by >7 days. Participants either remained seated for 7 h (SIT) or interrupted sitting with 3-min bouts of self-paced walking at 30-min intervals commencing 1 h after each meal (SIT-LESS). Physical activity, insulin regimen, experimental start times, and meal consumption were standardized during each arm. Plasma levels of interleukin (IL)-1β, tumour necrosis factor (TNF)-α, plasminogen activator inhibitor (PAI)-1 and fibrinogen were sampled at baseline, 3.5 and 7 h, and assessed for within- and between-group effects using a repeated measures ANOVA. The estimated glucose disposal rate was used to determine the insulin resistance status. Vascular-inflammatory parameters were comparable between SIT and SIT-LESS at baseline (p > .05). TNF-α, IL-1β, PAI-1 and fibrinogen increased over time under SIT, whereas these rises were attenuated under SIT-LESS (p < .001). Specifically, over the 7 h under SIT, postprandial increases were detected in TNF-α, IL-1β, PAI-1 and fibrinogen (+67%, +49%, +49% and +62%, respectively; p < .001 for all). Conversely, the SIT-LESS group showed no change in IL-1β (-9%; p > .50), whereas reductions were observed in TNF-α, PAI-1 and fibrinogen (-22%, -42% and -44%, respectively; p < .001 for all). The intervention showed enhanced effects in insulin-resistant individuals with T1D. Interrupting prolonged sitting with light-intensity activity ameliorates postprandial increases in vascular-inflammatory markers in T1D. The trial was prospectively registered (ISRCTN13641847).

Effect of a Single Light-intensity Walking Session on Sleep Quality of Patients with Bladder Cancer: A Randomized Cross-Over Study

ObjectivesExercise has been recommended to enhance sleep. However, there is a paucity of studies investigating the relationships between exercise and sleep problems in patients with bladder cancer. The authors explored the effects of a single bout of light-intensity walking on the sleep quality of patients with bladder cancer who have sleep disorders. Data SourcesA total of 14 patients with bladder cancer with sleep disorders were recruited for this trial. The participants were randomly assigned to the walking or control condition in a cross-over design to explore the effects of a single light-intensity walking session on objectively measured sleep quality. A two-way repeated measures analysis of variance and a nonparametric permutation test were used to examine intervention effects. Twelve participants (85.7%) completed the trial. A significant group × time interaction for sleep latency (P = .023) was identified. The pairwise comparison showed significant results (P = .012) for the difference between the post-test sleep latency and the pre-test. No significant group × time interactions were observed for the remaining seven sleep parameters. Additionally, only the main effects of time on length of awakening and time in bed were significant (P < .001). ConclusionA single bout of light-intensity walking has a positive effect on shortening the sleep latency of patients with bladder cancer who have sleep disorders. Implications for Nursing PracticeOncology nurses can encourage patients with bladder cancer to exercise, even light-intensity walking, which may improve sleep quality.

The Effects of Breaking Up Prolonged Sitting on Cognitive Performance in Middle‐Aged and Older Adults: Dose Response Analysis of a Randomized Crossover Trial

AbstractBackgroundSedentary behavior (SED) is highly prevalent and associated with poor health outcomes and cognitive decline, independent of physical activity (PA). Studies have established the harmful effects on cognition and information processing, and while PA guidelines endorse reducing SED, they fail to address how often SED should be broken up, and for how long. The purpose of this study is to assess how frequently and for how long SED should be disrupted with light‐intensity physical activity (PA) to offset the effects on cognitive performance.MethodA randomized crossover study of n = 11 middle and older aged adults (&gt;45 years) completed five 8‐hour visits: a sedentary (control) condition and four experimental conditions with varied walking (1.9 mph, 0% grade) frequency and durations: every 30 minutes for 1 minute, every 30 minutes for 5 minutes, every 60 minutes for 1 minute, and every 60 minutes for 5 minutes. Cognition was assessed at baseline, 4 hours, and 6 hours via the Single Digit Modalities Test (SDMT), a validated cognitive performance measure that assesses information processing speed and accuracy.ResultCompared with control, there was significant improvement in SDMT score for the every 30 minutes for 5 minutes dose (net difference compared to control: 3.1 [SE: 1.4], p‐value = 0.034), every 60 minutes for 1 minute dose (net difference compared to control: 3.4 [SE: 1.4], p‐value = 0.016), and every 60 minutes for 5 minutes dose (net difference compared to control: 3.3 [SE: 1.4], p‐value = 0.017). The effect on SDMT was not statistically significant for the every 30 minutes for 1 minute dose, but a positive trend was observed (net difference compared to control: 2.6 [SE: 1.4], p‐value = 0.069).ConclusionThere was a significant effect of breaking up SED on SDMT scores with light intensity walking for both low frequency breaks (1 minute every 60 minutes and for 5 minutes every 60 minutes) and high frequency breaks (5 minutes every 60 minutes). This suggests that even brief breaks in SED may offset harmful effects on cognitive performance. This result provides a specific and achievable mechanism for offsetting the harm caused by SED on cognitive performance.

Interrupting sitting acutely attenuates cardiometabolic risk markers in South Asian adults living with overweight and obesity.

This study examined the acute effects of interrupting sitting with light-intensity walking on postprandial cardiometabolic risk markers in South Asian adults. South Asians with overweight/obesity (n = 19; body mass index [BMI] > 23kg·m-2) and normal-weight (n = 8; BMI 18.0-22.9kg·m-2) aged 48.8 ± 5.6years completed two, 5-h conditions: (1) prolonged sitting (SIT), and (2) interrupted sitting with 5-min bouts of light-intensity walking every 30-min (INT-SIT). Blood samples and resting expired air samples were collected throughout each condition. Statistical analyses were completed using linear mixed models. In participants with overweight/obesity, postprandial glucose, triglycerides (TAG) and metabolic load index (MLI) over time were lower, whereas resting substrate utilisation and resting energy expenditure (REE) were higher, in INT-SIT than SIT (all p ≤ 0.05). Compared with SIT (0.18 [95% CI 0.13, 0.22] kcal.min-1), INT-SIT (0.23 [95% CI 0.18, 0.27] kcal.min-1) increased postprandial REE iAUC in participants with overweight/obesity (p = 0.04, d = 0.51). Postprandial TAG concentrations over time were lower in INT-SIT versus SIT (p = 0.01, d = 30) in normal-weight participants, with no differences in any other outcomes for this sample group. These findings suggest that interrupting sitting with 5-min bouts of light walking every 30-min acutely attenuates cardiometabolic risk markers among South Asians living with overweight/obesity, whereas limited effects may be seen in individuals with normal-weight.

O077 The Impact of Breaking up sitting during Simulated Nightshifts on Driving Performance during the Commute Home

Abstract Introduction The commute home from a nightshift is associated with increased accident risk. Driving performance strategies typically occur immediately before or during the commute, such as napping and caffeine. It is unknown whether strategies that target alertness throughout the nightshift could impact the commute home. Breaking up sitting with walking is an effective strategy to improve alertness during dayshifts. This study investigated the impact of breaking up sitting during the nightshift on driving performance post-shift. Method 41 adults (age M±SD: 24.4±4.6 years; 21 females) participated in a 7-day laboratory study, with 5 nightshifts (2200-0630). Participants were randomly allocated to: Breaking up sitting (BUS; n=21) or Sedentary (SED; n=20). Every 30-min during the nightshift BUS participants completed 3-min bouts of light-intensity walking, while SED participants remained sitting. At 2130 (pre-shift) and 0700 (post-shift) participants completed a 20-min simulated drive and the Karolinska Sleepiness Scale. Results Linear mixed models revealed a significant interaction between time (pre- or post-shift) and nightshift on driving performance and sleepiness, such that there was increased lane variability (p=0.03), speed variability (p&amp;lt;0.05), and sleepiness (p&amp;lt;0.05) post-shift compared to pre-shift, with performance worse on the first nightshift. There were no significant 2-way or 3-way interactions between condition (BUS or SED), time, or nightshift. Discussion Breaking up sitting with light-intensity walking did not improve performance for the commute home. However, given that breaking up sitting did not increase risk on the commute home, and it has benefits for cardiovascular health, it is an important strategy to promote to nightshift workers.

O073 The Relationship between Circadian type and Physical Activity on Cognitive Performance during Simulated Nightshifts: A Randomised Controlled Trial.

Abstract Introduction Physical activity might be a nonphotic strategy which could improve cognitive performance for nightshift workers. Innate characteristics like circadian type may also influence individual performance. Thus, this study explores the relationship between circadian type and physical activity on cognition over consecutive nightshifts. Methods Thirty-two healthy adults (age M±SD: 24.3±4.6 years; 19 females) participated in a 7-day laboratory study, with 5 nightshifts (2200-0600). Participants were randomised into the Breaking up sitting (BUS; n=19) or Sedentary (SED; n=13) condition. Overnight, BUS participants completed 3-min bouts of light-intensity walking every 30-min, while SED participants remained seated. At 2200, 0000, 0200, 0400 and 0600, participants completed the 10-min Psychomotor Vigilance Task (mean RRT). Participants completed the 11-item revised Circadian Type Inventory (factor 1: rigid/flexible; factor 2: languid/vigorous), resulting in four-subgroups (rigid; n= 12, flexible; n= 11, and languid; n= 11, vigorous; n= 13). Participants may only be one type from either factor (i.e. rigid and vigorous). Results Linear mixed models showed a significant 3-way interaction between nightshift (1-5), condition (BUS, SED), and circadian type (rigid/flexible) for mean RRT (p=0.03), such that flexible types in the Breaking up sitting condition outperformed Sedentary flexible types and Breaking up sitting rigid types, with performance worse on the first nightshift. There were no significant interactions between nightshift, condition and circadian type (languid/vigorous). Discussion Breaking up sitting improved performance for flexible types over rigid types. These findings have significant implications for nightshift rostering, suggesting that incorporating breaking up sitting may optimise cognitive performance, and therefore work efficiency.

On the move: The impact of breaking up sitting during the day on driving performance when sleep restricted

ObjectiveSleep restriction and prolonged sitting are both associated with reduced cognitive performance which is detrimental to safe driving. Regular bouts of walking to break up prolonged sitting have been shown to improve cognitive performance. It is unknown if breaking up sitting with walking may improve cognitive performance related to driving, particularly when drivers are sleep restricted. MethodsHealthy participants (n = 81, age 23.6 ± 4.5 years, 49% female) participated in a 7-day laboratory study (1 Adaptation day, 5 Experimental days, 1 Recovery day). Participants were randomly allocated to a condition: sitting 9 h sleep (Sit9), breaking up sitting 9 h sleep (Break9), sitting 5 h sleep (Sit5) and breaking up sitting 5 h sleep (Break5). Participants allocated to the Break9 and Break5 conditions completed 3-min of light-intensity walking on a treadmill every 30 min between 09:00–17:00 h, while participants in Sit9 and Sit5 groups remained seated during these times. Each participant completed a 20-min monotonous simulated driving commute at 08:10 h and 17:30 h on each of the 5 Experimental days. ResultsThere was a significant main effect of condition with decreased speed variability for Break9 compared to Sit9, Sit5 and Break5 (p < 0.0001) for both commutes. Break5 had significantly higher lane variability compared to Sit9 and Break9, and Sit5 (p = <0.05) for both commutes. Break5 reported greater subjective sleepiness before each commute compared to Sit9, Break9 and Sit5 (p < 0.001). Cox Proportional Hazards model showed a significant increase in time to first crash for Sit5 and Break5 compared to Sit9 (p= <0.005). There were no significant two- or three-way interaction effects by condition, day or commute time for any of the outcome measures. ConclusionThe findings from this study highlight that breaking up sitting with light-intensity walking may improve driving performance in areas such as speed maintenance, but may not extend to lane keeping performance. The findings also show that the benefits of breaking up sitting with light-intensity walking may not be sufficient to overcome detrimental impacts of sleep restriction for all areas of driving performance. Future research should focus on increased intensity of activity as a possible means to extend the benefits more comprehensively across additional areas of driving performance.

O065 The impact of breaking up sitting on vigilant attention during the workday when sleep restricted

Abstract Introduction Sleep restriction is associated with impairments to cognitive performance. A current strategy to improve cognitive performance at work is breaking up prolonged sitting with light-intensity walking. However, it is unknown whether this strategy can counteract the impact of sleep restriction. This study investigated the effect of breaking up sitting on cognitive performance under conditions of sleep restriction. Method 84 healthy adults (age M± SD 23.1±4.5 years; 41 females) participated in a 7-day laboratory study, with 5 simulated workdays (0900-1700). Participants were randomly allocated to a condition: Breaking up sitting and 9-h sleep (Break9; n=20), Breaking up sitting and 5h sleep (Break5; n=20), Sedentary and 9-h sleep (Sit9; n=22), Sedentary and 5-h sleep (Sit5; n=22). Sleep opportunity prior to each workday was 9-h (2200-0700) or 5-h (0200-0700) depending on condition. Every 30-min during the workday participants in the breaking up sitting conditions completed 3-min bouts of light-intensity walking, while participants in the sedentary conditions remained sitting. At 0900, 1100, 1300, 1500, and 1700, participants completed a 10-min Psychomotor Vigilance Task and the Karolinska Sleepiness Scale. Results Mixed model ANOVAs revealed no significant 2-way or 3-way interactions between condition (Break9, Break5, Sit9 and Sit5), time of day, and workday for vigilant attention (reciprocal mean response time and mean lapses) or subjective sleepiness. Discussion Breaking up prolonged sitting with light-intensity walking did improve cognitive performance. Higher doses of physical activity may be needed to counteract the effects of sleep restriction on cognitive performance. Findings highlight the acute cognitive deficits associated with inadequate sleep.

P126 The impact of inadequate sleep and breaking up sitting during the day on simulated driving performance

Abstract Introduction Inadequate sleep and prolonged sitting are both associated with a reduction in psychomotor functioning, a cognitive process crucial for the safety critical task of driving. Regular bouts of light-intensity physical activity have been shown to improve psychomotor function. However, it is unknown if breaking up sitting during the day can improve psychomotor functioning for the task of driving, particularly during the commute home when drivers may be at a higher risk of fatigue. Method Healthy participants (n=81, 49%female, age 23.6 ± 4.5 years ) participated in a 7-day laboratory study (1 adaptation, 5 experimental, 1 recovery). Participants were randomly allocated to a condition: sitting and 9-h sleep (Sit9; n=22), breaking up sitting 9-h sleep (Sit9; n=19), sitting and 5-h sleep (Sit5; n=21) and breaking up sitting 5-h sleep (Break5; n=19). Participants allocated the breaking up sitting conditions completed 3-min of light-intensity walking every 30 minutes between 09:00-17:00h, while participants in the sitting group remained seated. Driving performance was measured via speed and lane variability during a 20-min simulated drive at 08:10 and 17:30 for the 5 experimental days. Results Mixed model analyses revealed no significant interaction effects between condition and time of commute between Sit9, Break9, Sit5 and Break5 for driving performance. Discussion Breaking up sitting did not improve driving performance during the commute home. These findings highlight that light-intensity walking may not be adequate to overcome the effects of inadequate sleep on diving performance. Future studies should explore if higher intensity physical activity produce changes in driving performance.

Effects of interval-walking training on blood pressure in community-dwelling Japanese older adults.

The hypotensive effects of high-intensity interval training have been reported; however, studies on older adults are few. This study aimed to examine whether interval-walking training (IWT), a home-based program of high-intensity interval training, reduces blood pressure (BP) levels when compared with a non-intervention group in community-dwelling older adults. An intervention study was conducted with 55 men (age, 75±5 years; IWT/control groups, N.=27/28) and 100 women (75±5 years; N.=47/53). The IWT regimen was as follows: fast (high-intensity) walking at 70-85% of the peak aerobic capacity and normal (light-intensity) walking at approximately 40% of the peak aerobic capacity for 3 min each, ≥5 times/walking day, and ≥4 days/week for 5 months. Systolic, diastolic, and mean arterial BPs (SBP, DBP, and MAP, respectively) were measured in the supine posture. The mean baseline SBP/DBP was 132/78 mmHg in men and 131/72 mmHg in women. Five-month changes in SBP, DBP, or MAP did not significantly differ between the IWT and control groups in either sex. The weekly fast-walking time in the IWT group was negatively correlated with changes in DBP (Spearman's ρ=-0.383, P=0.049) and MAP (ρ=-0.444, P=0.021) only in men. Though present findings did not indicate significant hypotensive effects of IWT in community-dwelling older adults, men with longer fast-walking times experienced greater BP decreases. Further studies with sufficient sample sizes are needed to determine the factors modulating the effects of the proposed training program.

Effects of Multimodal Inpatient Rehabilitation vs Conventional Pulmonary Rehabilitation on Physical Recovery After Esophageal Cancer Surgery

ObjectiveTo determine the effects of multimodal rehabilitation initiated immediately after esophageal cancer surgery on physical recovery compared with conventional pulmonary rehabilitation. DesignRetrospective study. SettingPrivate quaternary care hospital. ParticipantsFifty-nine inpatients (N=59) who participated in either conventional pulmonary rehabilitation (n=30) or in multimodal rehabilitation (n=29) after esophageal cancer surgery were included. InterventionsBoth groups performed pulmonary exercises, including deep breathing, chest expansion, inspiratory muscle training, coughing, and manual vibration. In the conventional pulmonary rehabilitation group, light-intensity mat exercise, stretching, and walking were performed. The multimodal rehabilitation group performed resistance exercises and moderate- to high-intensity aerobic interval exercises using a bicycle. Main Outcome MeasuresThe European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire C30 (EORTC QLQ-C30), pain, 6-minute walk test (6MWT), 30-second chair stand test, and grip strengths were assessed before and after the rehabilitation programs. ResultsSymptom scales of pain, dyspnea, and insomnia in the EORTC QLQ-C30 as well as 6MWT improved significantly after each program (P<.05). 6MWT (73.1±52.6 vs 28.4±14.3, P<.001, d=1.15), 30-second chair stand test (3.5±3.9 vs 0.35±2.0, P<.001, d=1.06), and left grip strength (1.2±1.3 vs 0.0±1.5, P=.002, d=0.42) improved significantly in the multimodal rehabilitation group compared with the pulmonary rehabilitation group. While right grip strength also showed more improvement for those undergoing the multimodal program, the mean strength difference was not clinically meaningful. ConclusionsA multimodal inpatient rehabilitation program instituted early after esophageal cancer surgery improved endurance for walking more than conventional pulmonary rehabilitation as measured by the 6MWT and the 30-second chair stand test.

Mindful walking and cognition in older adults: A proof of concept study using in-lab and ambulatory cognitive measures

Mindfulness practice and walking have been linked individually to sustain cognition in older adults. This early-phase study aimed to establish proof-of-concept by evaluating whether an intervention that integrates light-intensity walking with mindfulness practices shows promising signs of improving cognition in older adults. Participants (N = 25, Mage = 72.4 ± 6.45) were community-dwelling older adults who engaged in a supervised mindful walking program over one month (8 sessions total, 2 sessions per week, 30-minute slow walking containing mindfulness skills). They completed performance-based and subjective ratings of cognitive measures in field before and after two mindful walking bouts using a smartphone app. They also completed in-lab performance-based and self-report cognitive measures at baseline and after the entire program. Controlling for demographics, potential covariates, and time trends, short-term improvements in perceived cognition and processing speed were observed from pre- to post-mindful walking sessions (i.e., 30 min) across multiple ambulatory cognitive measures (Cohen’s ds range = 0.46–0.66). Longer-term improvements in processing speed and executive function were observed between baseline and end of the program (i.e., one month) across various performance-based cognitive measures (ds range = 0.43–1.28). No significant changes were observed for other cognitive domains. This early-phase study (Phase IIa) provides preliminary support that mindful walking activity is promising for sustaining cognition in older adults. Our promising findings form the building blocks of evidence needed to advance this intervention to a fully powered randomized controlled trial that examines program efficacy with a comparator. Favorable outcomes will inform the development of this lifestyle behavioral strategy for promoting healthy brain aging in late adulthood.

Frequency of interruptions to prolonged sitting and postprandial metabolic responses in young, obese, Chinese men

ABSTRACT This study aimed to examine the effects of 3-min light-intensity walking every 30 min (3-min) and 6-min light-intensity walking every 60 min (6-min) compared with prolonged sitting (SIT) on the postprandial metabolic responses in young, centrally obese, Chinese men. Twenty-one Chinese men with central obesity (age, 23 ± 4 years; body mass index, 29.8 ± 3.2 kg·m−2; waist circumference, 98.7 ± 7.1 cm; mean ± SD) underwent three 6-h experiments with a 7-day washout period, SIT, 3-min, and 6-min, in randomized order. Compared with SIT, neither walking condition showed differences in total and net incremental area under the curve (tAUC and iAUC, respectively) for glucose, insulin, nor non-esterified fatty acids. The tAUC and iAUC for triglycerides for the SIT condition (10.8 [9.3, 12.2] and 4.4 [3.7, 5.1] mmol·h·L−1, respectively; mean [95% confidence interval]) was higher than 3-min (10.4 [9.0, 11.8] and 3.8 [3.3, 4.3] mmol·h·L−1, respectively, both Ps <0.05) and 6-min (9.6 [8.1, 11.0] and 3.5 [2.9, 4.2] mmol·h·L−1, respectively, both Ps <0.01) conditions. Interrupting prolonged sitting regardless of frequency-reduced postprandial triglycerides. A higher volume of physical activity may be required to obtain greater glycaemic benefits in young Chinese men with central obesity.