Steven Noel Blair

(1) Background: Sleep, a physiological necessity, has strong inflammatory underpinnings. Diet is a strong moderator of systemic inflammation. This study explored the associations between the Dietary Inflammatory Index (DII^®) and sleep duration, timing, and quality from the Energy Balance Study (EBS). (2) Methods: The EBS (n = 427) prospectively explored energy intake, expenditure, and body composition. Sleep was measured using BodyMedia’s SenseWear^® armband. DII scores were calculated from three unannounced dietary recalls (baseline, 1-, 2-, and 3-years). The DII was analyzed continuously and categorically (very anti-, moderately anti-, neutral, and pro-inflammatory). Linear mixed-effects models estimated the DII score impact on sleep parameters. (3) Results: Compared with the very anti-inflammatory category, the pro-inflammatory category was more likely to be female (58% vs. 39%, p = 0.02) and African American (27% vs. 3%, p < 0.01). For every one-unit increase in the change in DII score (i.e., diets became more pro-inflammatory), wake-after-sleep-onset (WASO) increased (βChange = 1.00, p = 0.01), sleep efficiency decreased (βChange = −0.16, p < 0.05), and bedtime (βChange = 1.86, p = 0.04) and waketime became later (βChange = 1.90, p < 0.05). Associations between bedtime and the DII were stronger among African Americans (βChange = 6.05, p < 0.01) than European Americans (βChange = 0.52, p = 0.64). (4) Conclusions: Future studies should address worsening sleep quality from inflammatory diets, leading to negative health outcomes, and explore potential demographic differences.

Background: We examined the effect of power training on habitual, intervention and total physical activity (PA) levels in older adults with type 2 diabetes and their relationship to metabolic control. Materials and Methods: 103 adults with type 2 diabetes were randomized to receive supervised power training or sham exercise three times/week for 12 months. Habitual, intervention, and total PA, as well as insulin resistance (HOMA2-IR) and glycosylated hemoglobin (HbA1c), were measured. Results: Participants were aged 67.9 ± 5.5 yrs, with well-controlled diabetes (HbA1c = 7.1%) and higher than average habitual PA levels compared to healthy peers. Habitual PA did not change significantly over 12 months (p = 0.74), and there was no effect of group assignment on change over time in habitual PA over 0–6 (p = 0.16) or 0–6–12 months (p = 0.51). By contrast, intervention PA, leg press tonnage and total PA increased over both 6- and 12-month timepoints (p = 0.0001), and these changes were significantly greater in the power training compared to the sham exercise group across timepoints (p = 0.0001). However, there were no associations between changes in any PA measures over time and changes in metabolic profile. Conclusion: Structured high-intensity power training may be an effective strategy to enhance overall PA in this high-risk cohort.

Background: Many older adults in the U.S. do not achieve the recommended amount of physical activity (PA) to fully realize a myriad of health benefits. Adiposity is one of those important correlates of PA and sedentary behaviors. However, the full extent to which adiposity is associated with PA and stationary time (STA) is uncertain. Therefore, we examined the association of adiposity with objectively measured PA and STA in black and white older adults. Methods: We conducted a cross-sectional study of older adults enrolled in the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study 2003–2007 who participated in an ancillary accelerometer study 2009–2013. Assessment of body mass index (BMI) and waist circumference (WC) was completed during an in-home visit in the parent study. PA was measured by Actical™ accelerometers, which provided estimates of moderate-to-vigorous-intensity PA (MVPA), light-intensity PA (LPA), and STA for 4–7 consecutive days. Data from accelerometers were standardized to square root percentages of total wear time per day (SqrtMVPA%, SqrtLPA%, and SqrtSTA%). Interactions were tested for BMI and WC by race and sex, separately. Results: Data were available for 7873 participants (69.8 ± 8.7 yr, 54.2% women, 31.5% African American). In mixed linear regression models, significant interactions existed in BMI by race and sex for the SqrtMVPA%, WC by race and sex for the SqrtMVPA% and the SqrtLPA% model(p < 0.05). No interaction was significant for the logistic model of meeting the PA guideline or not. In subgroup analyses, BMI was inversely associated with SqrtMVPA%, SqrtLPA%, and positively related to SqrtSTA% in black women, white men and white women after adjustments. Similar patterns were observed between WC and SqrtMVPA%, SqrtLPA%, and SqrtSTA% in all groups, respectively. However, BMI was not associated with SqrtMVPA% in black men. Those with higher BMI or WC were less likely to meet the PA guideline in all groups. Conclusions: Adiposity was inversely associated with higher levels of MVPA/LPA and positively associated with higher levels of STA among black and white older adults. Prevention efforts aimed at promoting weight control may be beneficial to prevent physical inactivity and sedentary lifestyle among older adults.

Objectives: To examine the independent, joint, and fully combined associations of sedentary behavior (SB), moderate-to-vigorous physical activity (MVPA), and cardiorespiratory fitness (CRF) with the odds of poor sleep quality (SQ). Methods: We performed a secondary data analysis on 757 working adults (male = 345) in Singapore, with an average age of 35.2 years. The Pittsburgh Sleep Quality Index was used to assess SQ. Objectively measured MVPA and SB were each obtained using an accelerometer. A non-exercise prediction equation was used to estimate CRF. Logistic regression models were used to determine associations. Results: In total, 13.2% of the sample (n = 100) was identified as having poor SQ. After adjusting for study covariates, independent analyses revealed a clear inverse association for higher CRF and lower odds of poor SQ (OR = 0.50; 95% CI = 0.28–0.91). SB and MVPA demonstrated no independent associations. Joint associations revealed that odds of having poor SQ for those with low CRF was higher regardless of SB level and was further deteriorated by lower MVPA in the fully combined model. The fully combined model also demonstrated that those with lower SB, higher MVPA, and higher CRF had the lowest odds of having poor SQ (OR = 0.28; 95% CI = 0.10–0.78). Conclusions: Physical activity/exercise training programs that aim to improve CRF may be useful in lowering the odds or poor SQ in working adults.

This study aimed to examine the relationship between pedometer-assessed daily step count and all-cause mortality in a sample of elderly Japanese people. Participants included 419 (228 males and 191 females) physically independent, community-dwelling 71-year-old Japanese people. The number of steps per day was measured by a waist-mounted pedometer for seven consecutive days at baseline. Participants were divided into quartiles based on their average number of steps/day (first quartile, < 4503 steps/day; second quartile, 4503–6110 steps/day; third quartile, 6111–7971 steps/day; fourth quartile, > 7972 steps/day) and were followed up over a mean period of 9.8 years (1999–2010) for mortality. Seventy-six participants (18.1%) died during the follow-up period. The hazard ratios (adjusted for sex, body mass index, cigarette smoking, alcohol intake, and medication use) for mortality across the quartiles of daily step count (lowest to highest) were 1.00 (reference), 0.81 (95%CI, 0.43–1.54), 1.26 (95%CI, 0.70–2.26), and 0.46 (95%CI, 0.22–0.96) (P for trend = 0.149). Participants in the highest quartile had a significantly lower risk of death compared with participants in the lowest quartile. This study suggested that a high daily step count is associated with a lower risk of all-cause mortality in physically independent Japanese elderly people.

Rationale: Physical inactivity among patients with chronic obstructive pulmonary disease is associated with exacerbations requiring high-cost health care utilization including urgent, emergent, and hospital care. Objectives: To examine the effectiveness of a behavioral lifestyle physical activity intervention combined with chronic obstructive pulmonary disease self-management education to prevent high-cost health care utilization. Methods: This was an analysis of secondary outcomes of the Chronic Obstructive Pulmonary Disease Self-Management Activation Research Trial, a two-arm randomized trial of stable adult outpatients with chronic obstructive pulmonary disease recruited from primary care and pulmonary clinics. Following a 6-week self-management education run-in period, participants were randomized to usual care or to a telephone-delivered home-based health coaching intervention over 20 weeks. Secondary outcomes of physical activity and health care utilization were determined by self-report 6, 12, and 18 months after randomization. Associations between treatment allocation arm and these secondary outcomes were examined using log-binomial and Poisson regression models. Results: A total of 325 outpatients with stable chronic obstructive pulmonary disease were enrolled in the trial. Their average age was 70.3 years (standard deviation, 9.5), and 50.5% were female; 156 were randomized to usual care and 149 to the intervention. A greater proportion of participants reported being persistently active over the 18-month follow-up period in the intervention group (73.6%) compared with the usual care group (57.8%) (mean difference, 15.8%; 95% confidence interval, 4.0–27.7%). This association varied by severity of forced expiratory volume in 1 second impairment (P for interaction = 0.09). Those in the intervention group with moderate impairment (forced expiratory volume in 1 second, 50–70% predicted), more frequently reported being persistently active compared with the usual care (86.0 vs. 65.1%; mean difference, 20.9%; 95% confidence interval, 5.7–36.1%). Patients with severe and very severe forced expiratory volume in 1 second impairment (forced expiratory volume in 1 second < 50% predicted) in the intervention group also reported being persistently active more frequently compared with usual care (63.3 vs. 50.8%; mean difference, 12.6%; 95% confidence interval, –4.7 to 29.8). The intervention was associated with a lower rate of lung-related utilization (adjusted rate ratio, 0.38; 95% confidence interval, 0.23–0.63) only among participants with severe spirometric impairment. Conclusions: Our results demonstrate that a feasible and generalizable home-based coaching intervention may decrease sedentary behavior and increase physical activity levels. In those with severe chronic obstructive pulmonary disease, this intervention may reduce lung disease–related health care utilization. Clinical trial registered with www.clinicaltrials.gov (NCT01108991).

Although total sedentary time has been associated with increased mortality, most studies have relied on participant recall to report activity. Whether longer or shorter bouts of inactivity are asso... Background: Excessive sedentary time is ubiquitous in Western societies. Previous studies have relied on self-reporting to evaluate the total volume of sedentary time as a prognostic risk factor fo...