Exploring Determinants of Exercise-Related Affective Valence in Regular Exercisers Between the Ages of 55 and 69 Years.

This study aimed to understand determinants of recalled in-task affective valence experienced during a regularly performed aerobic bout in adult exercisers aged 55+. Qualitative data were collected (January to March, 2021, during the COVID-19 pandemic) using interviews wherein individuals (N = 16, 69% women, 61 ± 5 years) recalled deviations in affective valence in response to a regularly completed bout. Using thematic analyses, two themes emerged regarding how COVID-19 impacted regular exercise behaviors: (a) "loss" and (b) "adaptation." Two themes encompassed the determinants of recalled in-task affective valence: (a) "person-specific conditions" and (b) "external conditions." Finally, an increase in duration/intensity during a pleasant session was indicated by 44% of the participants, while 75% indicated a decrease in duration/intensity during an unpleasant session. The participants indicated that affective valence was determined by previously cited and novel factors that relate to exercise performed in naturalistic environments. Volitional modifications to planned exercise volume appear more responsive to feelings of displeasure.

"It was just for us": qualitative evaluation of an exercise intervention for African-American couples.

BACKGROUND: Promoting long-term exercise adherence should be a key focus for health and fitness professionals working to reduce obesity and cardiometabolic health disparities, and all-cause mortality in inactive African-American (AA) adults. Data have suggested that romantic partners can improve long-term exercise adherence and that this dyadic approach should be examined in exercise interventions. Therefore, the purpose of this study was to conduct a qualitative evaluation of a pilot exercise intervention conducted in older AA couples. METHODS: Two semi-structured focus groups were utilized to compare participants' perceptions of and experiences during the pilot intervention across two randomly assigned treatment conditions (exercising together with partner [ET; n = 8] versus exercising separately [ES: n = 6]). Participants (mean age: 64.7 ± 6.8 years) of a previous 12-week pilot exercise intervention (walking ≥3 days/week, 30 min/day plus supervised resistance training 2 days/week) were interviewed. Verbatim transcripts were coded using an open coding approach. RESULTS: Three key themes (intervention value/benefits, intervention difficulties, and suggested improvements) emerged. Although all couples identified health and relationship benefits of the intervention, some differences surfaced within themes across the two intervention groups. CONCLUSIONS: Overall, these qualitative data suggest that couples had a positive experience while participating in the pilot study. In addition, key learning points to improve the intervention were identified including a more gradual transition to independent exercise, more flexibility training, and the incorporation of tangential education. These data will help investigators continue to develop the intervention, which is ultimately designed to promote long-term exercise adherence to reduce cardiometabolic health disparities in the AA community.

Ratings of Perceived Exertion During Walking Predicts Endurance Independent of Physiological Effort in Older Women.

Hunter, GR, Neumeier, WH, Chandler-Laney, PC, Carter, SJ, Borges, JH, Hornbuckle, LM, Plaisance, EP, and Fisher, G. Ratings of perceived exertion during walking predicts endurance independent of physiological effort in older women. J Strength Cond Res 34(5): 1340-1344, 2020-This study aimed to determine whether ratings of perceived exertion (RPE) and physiological effort at different exercise intensities relate to exercise endurance. Ninety-eight sedentary women (older than 60 years) completed 3 submaximal locomotion tasks: (a) stair climbing, (b) flat walking at 2 mph, and (c) grade walking at 2 mph. Maximal treadmill endurance was measured at least 3 days before the submaximal tests. Oxygen uptake was measured during all tests, and RPE were collected for the submaximal tasks. Ratings of perceived exertion during moderate-intensity exercise (walking on the flat at 43% V[Combining Dot Above]O2max, partial R = -0.35, p < 0.01), but not higher intensity exercise (grade walk at 59% V[Combining Dot Above]O2max, p = 0.49, and stair climbing at 67% V[Combining Dot Above]O2max, p = 0.17), were related to endurance even after adjusting for aerobic capacity and physiological effort (composite of maximal heart rate, ventilation, and respiratory exchange ratio). However, physiological effort was significantly related to endurance for the higher intensity exercise (both grade walk and stair climbing partial R >-0.24, p < 0.02). Similar to previous findings that subjective ratings of fatigue at rest were related to RPE during low/moderate-intensity exercise, but not higher intensity exercise, these data further support Ekkekakis's dual-mode hypothesis that cognitive factors influence RPE during low/moderate-intensity exercise. A practical application is that the coach and personal trainer should know that physiological effort seems to play a greater role in influencing endurance than RPE as intensity of exercise increases.

Engaging a Community Advisory Board to Inform an Exercise Intervention in Older African-American Couples.

This paper describes our approach to forming and engaging a community advisory board (CAB) to assist in the development of a proposed exercise intervention pilot study. The intervention aimed to examine the effects of exercise on exercise adherence, the provision of partner support and receptivity to partner health influence, and cardiometabolic risk in older African-American romantic couples. CAB invitations were extended to local community members and leaders who had a stake in the health of the target population. Seven individuals accepted the invitation and attended at least one of two CAB meetings during which we proposed ideas for the exercise intervention pilot study, then solicited CAB input in four key areas related to the study including: (1) priority health concerns of the target population, (2) the intervention protocol and methodologies, (3) cultural relevance, and (4) sustainability. Two investigators jointly led both CAB meetings, which lasted approximately 3 h each. Recorded community feedback was summarized and coded using a thematic analysis approach. Themes were identified and agreed upon within the four areas identified above. Overall, the proposed study was well-received by the CAB and considered beneficial for and relevant to the target population. Although not all suggestions put forth by the CAB were feasible given the inherent limitations of pilot work, we made multiple study modifications as a result of CAB recommendations. Further, all CAB feedback helped inform plans to launch the intervention on a larger scale and were vital in ensuring that the pilot study was valued in the local community. Although community-based participatory research that originates within a community may be preferable, we demonstrate the utility of a community-partnered approach to intervention design in a vulnerable population. This model could assist researchers who wish to engage the local community to help develop a preliminary idea for a health-related intervention.

If He Is in Shape, So Is the Marriage: Perceptions of Physical Fitness and Exercise and Older Couples' Marital Functioning.

The current study explored concordance in spouses' perceptions about exercise and how these perceptions predicted observed and self-reported marital functioning using a sample of 64 older married couples. Although couples were similarly motivated to exercise, their views on their physical fitness and potential barriers to exercise were uncorrelated. Dyadic analyses suggested that spouses' exercise perceptions, particularly husbands', were associated with how spouses treated each other during a marital problem-solving task and with their concurrent and future marital satisfaction. Exploring how spouses' views of exercise are related to their marital functioning and for whom these links are most salient may highlight potential opportunities and challenges for those wishing to strengthen couples' individual and relational well-being through exercise.

Effects of high-intensity interval training on cardiometabolic risk in overweight and obese African-American women: a pilot study.

OBJECTIVE: Little is known about high-intensity interval training (HIIT) in African-American (AA) women. The purpose of this pilot study was to evaluate the effects of HIIT and steady-state (SS) exercise on cardiometabolic risk factors in young AA women. DESIGN: A 16-week exercise intervention was conducted 3x/week. Twenty-seven AA women were randomized to SS (n = 11; 32 continuous minutes of treadmill walking at 60-70% of maximum heart rate (HRmax)), or HIIT (n = 16; 32 min of treadmill HIIT alternating 3 min at 60-70% of HRmax with 1 min at 80-90% of HRmax). Two-way repeated measures ANOVA with intention-to-treat analysis was used to identify changes between groups. Significance was accepted at P ≤ 0.05. RESULTS: Of the 27 women who entered the study (age: 30.5 ± 6.8 years; BMI: 35.1 ± 5.1 kg/m2; 5274 ± 1646 baseline steps/day), 14 completed the intervention. HIIT significantly decreased waist circumference (107.0 ± 11.3 to 105.1 ± 11.9 cm) compared to SS, which showed no change. There was a significant time effect for steps where HIIT increased steps/day (5334 ± 1586 to 7604 ± 1817 steps/day), and SS had no change. There were no significant changes in either group for any other measurements. CONCLUSION: HIIT was more effective at reducing waist circumference and increasing daily steps/day than SS treadmill exercise over 16 weeks. Further research in a larger sample is indicated to evaluate the effects of each protocol on cardiometabolic risk factors.

Body composition and muscular strength as predictors of bone mineral density in African American women with metabolic syndrome.

Our cross-sectional study investigated the relationships between regional bone mineral density (BMD) and body composition variables, including total body lean mass (LM) and fat mass (FM), as well as muscular strength in overweight and obese African-American (AA) women with metabolic syndrome (MetS). Forty-four women ranging in age from 39 to 61 years participated. Upper and lower body strength measurements were assessed using chest press and leg extension exercises, respectively. Body composition and BMD of the total body, spine (L2-L4), hip, and radius were measured by dual-energy X-ray absorptiometry. LM was positively correlated with total body, spine, hip, and radius BMD (r = .338-.603, all P < .05), and FM was positively correlated with total body BMD (r = .343, P < .05). In multiple linear regression analyses after controlling for age, height, total energy, and calcium intake, LM was a significant positive determinant of BMD at various skeletal sites (P < .05), while FM was negatively related to BMD of total hip (P < .05). Our results indicate that LM is an independent predictor of total body, spine, hip, and total radius BMD. In contrast, FM is a negative predictor of total body and hip BMD in overweight or obese AA women with MetS (P < .05). Upper and lower body muscular strength measures were not associated with BMD at any skeletal sites. These results suggest an important role for LM in preventing the development of osteopenia and osteoporosis.

Translating the Dietary Approaches to Stop Hypertension (DASH) diet for use in underresourced, urban African American communities, 2010.

INTRODUCTION: Randomized trials have demonstrated the effectiveness of the Dietary Approaches to Stop Hypertension (DASH) program for lowering blood pressure; however, program participation has been limited in some populations. The objective of this pilot study was to test the feasibility of using a culturally modified version of DASH among African Americans in an underresourced community. METHODS: This randomized controlled pilot study recruited African Americans in 2 North Carolina neighborhoods who had high blood pressure and used fewer than 3 antihypertension medications. We offered 2 individual and 9 group DASH sessions to intervention participants and 1 individual session and printed DASH educational materials to control participants. We collected data at baseline (March 2010) and 12 weeks (June 2010). RESULTS: Of 152 potential participants, 25 were randomly assigned to either the intervention (n = 14) or the control (n = 11) group; 22 were women, and 21 were educated beyond high school. At baseline, mean blood pressure was 130/78 mm Hg; 19 participants used antihypertension medications, and mean body mass index was 35.9 kg/m(2). Intervention participants attended 7 of 9 group sessions on average. After 12 weeks, we observed significant increases in fruit and vegetable consumption and increases in participants' confidence in their ability to reduce salt and fat consumption and eat healthier snacks in intervention compared with control participants. We found no significant decreases in blood pressure. CONCLUSION: Implementation of a culturally modified, community-based DASH intervention was feasible in our small sample of African Americans, which included people being treated for high blood pressure. Future studies should evaluate the long-term effect of this program in a larger sample.

Key takeaways for knowledge expansion of early-career scientists conducting Transdisciplinary Research in Energetics and Cancer (TREC): a report from the TREC Training Workshop 2022.

The overall goal of the annual Transdisciplinary Research in Energetics and Cancer (TREC) Training Workshop is to provide transdisciplinary training for scientists in energetics and cancer and clinical care. The 2022 Workshop included 27 early-to-mid career investigators (trainees) pursuing diverse TREC research areas in basic, clinical, and population sciences. The 2022 trainees participated in a gallery walk, an interactive qualitative program evaluation method, to summarize key takeaways related to program objectives. Writing groups were formed and collaborated on this summary of the 5 key takeaways from the TREC Workshop. The 2022 TREC Workshop provided a targeted and unique networking opportunity that facilitated meaningful collaborative work addressing research and clinical needs in energetics and cancer. This report summarizes the 2022 TREC Workshop's key takeaways and future directions for innovative transdisciplinary energetics and cancer research.

Evidence for the association between abdominal fat and cardiovascular risk factors in overweight and obese African American women.

OBJECTIVE: To determine the association between total body fat and abdominal region fat derived from dual-energy x-ray absorptiometry (DXA) scans and cardiovascular disease (CVD) risk factors in middle- to older-aged African American (AA) women. We also compared tape-measured waist and hip circumference and their ratio (WHR) with DXA measurements in the context of CVD risk factor predictability. METHODS: Participants included 59 overweight or obese African American women (age, 48.7 ± 5.6 years). Anthropometries, including waist and hip circumferences, were measured, and DXA scans were used to derive fat mass from the total body and abdominal region. Blood analyses included glucose, total cholesterol, triglycerides, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, total cholesterol/HDL and LDL/HDL ratios, C-reactive protein (CRP), and fibrinogen. Multiple linear regression models were used to investigate the association among DXA-derived fat mass measures, waist circumference, WHR, and cardiovascular risk factors. RESULTS: Among DXA-derived fat mass measures, DXA-derived abdominal fat mass showed the best prediction for glucose and triglycerides, although waist circumference and DXA-derived abdominal fat mass had equivalent capacity for predicting the total cholesterol/HDL ratio. Furthermore, waist circumference showed the best prediction for LDL/HDL ratio and CRP. CONCLUSIONS: Both DXA-derived abdominal fat mass and waist circumference had comparable capacity for predicting blood lipid profiles and CRP. Therefore, if waist circumference is measured correctly, it could be used as the simplest means of predicting CVD risk factors in overweight/obese AA women when DXA is not available.

African American Couples' Experiences during an Exercise Intervention Interrupted by the COVID-19 Pandemic: A Qualitative Case Study.

Exercise intervention researchers often struggle to transition participants from supervised/laboratory-based exercise to independent exercise. Research to inform this critical juncture remains underdeveloped. This qualitative case study investigated the transition from laboratory-based to home-based training in a subset of middle-aged and older African American couples whose exercise intervention experience was interrupted by the COVID-19 pandemic. All four couples (N = 8) whose study participation was interrupted participated in dyadic interviews by videoconference. Two investigators independently reviewed verbatim transcripts, and then used an iterative open coding approach to identify themes from the qualitative data. Three main themes were identified: (1) resistance training program modifications, (2) partner interactions, and (3) external pandemic-related factors. Each theme included both positive and negative feedback related to participants' experiences. Overall, virtual, home-based training appeared acceptable and feasible in this group. Further research is needed to investigate the utility of virtual training to effectively transition participants from laboratory-based to independent exercise.

Running while Black: A distinctive safety concern and barrier to exercise in White neighborhoods.

While literature has shown that some Black Americans cite safety concerns as a barrier to outdoor activity in their neighborhoods for reasons related to violence, limitations in the built environment (e.g., lack of sidewalks), and even unleashed dogs, recent national events suggest that attention should also be directed toward the safety concerns of Black Americans living in neighborhoods that do not involve the commonly referenced issues above. In this timely commentary, the unique personal perspectives and internal dialogue of Black exercisers while navigating predominantly White neighborhoods, particularly those of higher socioeconomic status are discussed. This piece also includes discussion of how racial profiling incites hypervigilance and often fear in Black Americans attempting to exercise outdoors in White spaces. This is problematic, as it can discourage this incredibly positive health behavior that has been shown to mitigate obesity, cardiometabolic risk, and several other health disparities that continue to afflict Black communities. A collaborative effort inclusive of physical activity, public health/health disparity, and social science researchers is warranted to build a body of current scientific literature that elucidates and explores this particular safety concern in various Black outdoor enthusiasts.

EPOC Comparison Between Resistance Training and High-Intensity Interval Training in Aerobically Fit Women.

Previous research has shown that various modes of exercise may elicit significant increases in resting metabolism for up to 24 hours post-exercise, but typically using untrained or moderately active subjects. The purpose of the present study was to compare excess post-exercise oxygen consumption (EPOC) between circuit-style resistance training (RT) and high-intensity interval training (HIIT) in young, aerobically fit women. During the follicular phase of the menstrual cycle, seven participants reported to the laboratory for evening and morning baseline resting metabolic rate (RMR) measurements via indirect calorimetry. Participants fasted and slept overnight in the laboratory between RMR measurements. Following the morning RMR measurement, participants were randomly assigned to complete either a total-body, circuit-style RT protocol (30 seconds of lifting at 80% 1RM:one minute rest) or treadmill HIIT (30-second run at 90% VO2 max:one minute stationary recovery). RMR was repeated 14 and 24 hours post-exercise. All procedures were replicated during the follicular phase of the next menstrual cycle using the remaining exercise protocol. Resting VO2 was significantly (p<0.05) higher 14 hours after RT (3.8±0.3 ml/kg/min) compared to baseline (3.4±0.3 ml/kg/min), however HIIT showed no significant change (3.7±0.3 ml/kg/min). Both RT and HIIT showed significantly higher energy expenditure 14 hours post-exercise (33±5 and 33±4 kcals/30 minutes, respectively) compared to baseline (30±3 kcal). Neither protocol sustained a RMR change at 24 hours. Based on the magnitude and duration of post-exercise energy expenditure, EPOC responses may be a worthwhile consideration when prescribing exercise for weight maintenance in young, fit women.

Better Together? A Pilot Study of Romantic Partner Influence on Exercise Adherence and Cardiometabolic Risk in African-American Couples.

BACKGROUND: African-Americans (AAs) have higher rates of inactivity, obesity, and cardiometabolic risk compared to other races/ethnicities. Romantic partners can positively influence health habits, yet whether or not couples have to exercise together in order to adopt regular exercise remains unclear. This study examined whether exercising together influences exercise adherence and cardiometabolic risk in AA couples. METHODS: Nine AA romantic couples (age 62.8 ± 7.7 years; body mass index 31.0 ± 4.4 kg/m2; 6105 ± 1689 average steps/day) completed a 12-week walking (≥ 30 min, 3 days/week) plus resistance training (RT; 2 days/week) pilot intervention. Couples were randomized to either exercise together (ET) or separately (ES). Waist and hip circumferences, iDXA-measured body composition, blood pressure, and blood biomarkers (glucose, hemoglobin A1c (HbA1c), total cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides, C-reactive protein, and fibrinogen) were assessed pre- and post-intervention. Independent-sample t tests and generalized linear mixed models, controlling for gender, were used to analyze data. Significance was accepted at P < 0.05. RESULTS: There were no significant group × time interactions for any outcome. However, ET trended toward more walking (86.5 ± 57.7 min/week) than ES (66.1 ± 31.7 min/week). There were also significant overall time effects for waist circumference (P < 0.001), body fat (P = 0.020), fat mass (P = 0.007), gynoid fat (P = 0.041), HbA1c (P = 0.020), and HDL (P = 0.047), where all variables decreased. CONCLUSIONS: Trends showed exercising together may promote walking prescription adherence, although more research is needed in a larger sample. This intervention may also improve cardiometabolic risk factors in this population. These pilot data will inform the current investigators' future exercise intervention research in AA adult dyads.

Effects of static stretching on energy cost and running endurance performance.

Stretching before anaerobic events has resulted in declines in performance; however, the immediate effects of stretching on endurance performance have not been investigated. This study investigated the effects of static stretching on energy cost and endurance performance in trained male runners. Ten trained male distance runners aged 25 +/- 7 years with an average VO2max of 63.8 +/- 2.8 ml/kg/min were recruited. Participants reported to the laboratory on 3 separate days. On day 1, anthropometrics and VO2max were measured. On days 2 and 3, participants performed a 60-minute treadmill run randomly under stretching or nonstretching conditions separated by at least 1 week. Stretching consisted of 16 minutes of static stretching using 5 exercises for the major lower body muscle groups, whereas nonstretching consisted of 16 minutes of quiet sitting. The run consisted of a 30-minute 65% VO2max preload followed by a 30-minute performance run where participants ran as far as possible without viewing distance or speed. Total calories expended were determined for the 30-minute preload run, whereas performance was measured as distance covered in the performance run. Performance was significantly greater in the nonstretching (6.0 +/- 1.1 km) vs. the stretching (5.8 +/- 1.0 km) condition (p < 0.05), with significantly greater energy expenditure during the stretching compared with the nonstretching condition (425 +/- 50 vs. 405 +/- 50 kcals). Our findings suggest that stretching before an endurance event may lower endurance performance and increase the energy cost of running.

A Faith-Integrated Physical Activity Intervention and Cardiometabolic Risk in African American Women.

PURPOSE: To determine the effects of a 10-month secular (SEC) versus faith-integrated (FI) community-based physical activity (PA) intervention on cardiometabolic risk factors in low active, African-American women. METHODS: Participants (age: 55.4±11.6 years; body mass index (BMI): 36.0±7.9 kg/m2; average baseline steps/day: 3,807±1,250) from a larger study (n=418) participated in a sub-study to measure cardiometabolic disease indicators (primary outcomes) and PA (secondary outcomes) pre- and post-intervention (SEC: n=42; FI: n=43). Height, weight, waist and hip circumferences, resting blood pressure, hemoglobin A1c, average steps/day, sedentary behavior, light-intensity physical activity (LPA), and moderate-to-vigorous-intensity physical activity (MVPA) were acquired at baseline and 10 months. Multivariate generalized linear mixed models that included churches as a random effect were used to compare mean changes in outcomes at 10 months between the two study groups (α=0.05). RESULTS: The FI group showed significant time effects for weight (93.4±2.4 to 92.2±2.3 kg), BMI (35.7±1.0 to 35.3±1.0 kg/m2), and waist circumference (106.9±2.2 to 103.8±2.5 cm), while the SEC group had a significant time effect for hip circumference (121.6±1.9 to 119.9±1.7 cm). There were no time effects in either group for blood pressure, hemoglobin A1c, steps/day, sedentary time, or MVPA. FI significantly decreased LPA in both 1-minute activity bouts (641±13 to 588±16 minutes/day) and 10-minute bouts (536±11 to 479±15 minutes/day). There were no significant differences between SEC and FI for any variable. CONCLUSIONS: The improvements in body weight, BMI, and waist circumference shown after the FI intervention could have long-term implications on cardiometabolic health, particularly if exercise is continued. Further research is needed to examine the effects of culturally-relevant interventions on chronic disease indicators in African-American women, particularly those established as high risk for cardiometabolic disease.

Associations between measures of health-related physical fitness and cardiometabolic risk factors in college students.

OBJECTIVE: To determine the influence of health-related fitness on cardiometabolic risk factors in college students. PARTICIPANTS: 75 traditional students (33 men and 42 women, 21.8±1.8 years old) at a university in southeastern U.S. METHODS: Height, weight, waist circumference, body composition, blood pressure, lipids, glucose, insulin, c-reactive protein, and glucose tolerance were measured. Indices of insulin sensitivity were calculated. Aerobic and muscular fitness were measured. Regression and correlation analyses, and comparisons of cardiometabolic markers in low- vs high-fit participants were performed. RESULTS: Men and women with low muscular fitness exhibited higher fasting insulin, and poorer insulin sensitivity index scores than those with high muscular fitness. In addition, women with high body fat percentage exhibited higher fasting and 2-hour insulin levels and lower insulin sensitivity index scores than those with low body fat percentages. CONCLUSIONS: College students possessing low levels of health-related physical fitness exhibited less favorable cardiometabolic risk profiles.

Protective role of physical activity on type 2 diabetes: Analysis of effect modification by race-ethnicity.

BACKGROUND: It is well known physical activity (PA) plays a role in the prevention of type 2 diabetes (T2D). However, the extent to which PA may affect T2D risk among different race-ethnic groups is unknown. Therefore, the aim of the present study was to systematically examine the effect modification of race-ethnicity on PA and T2D. METHODS: The PubMed and Embase databases were systematically searched through June 2016. Study assessment for inclusion was conducted in three phases: title review (n = 13 022), abstract review (n = 2200), and full text review (n = 265). In all, 27 studies met the inclusion criteria and were used in the analysis. Relative risks (RRs) and 95% confidence intervals (CIs) were extracted and analyzed using Comprehensive Meta-Analysis software. All analyses used a random-effects model. RESULTS: A significant protective summary RR, comparing the most active group with the least active PA group, was found for non-Hispanic White (RR 0.71, 95% CI 0.60-0.85), Asians (RR 0.76, 95% CI 0.67-0.85), Hispanics (RR 0.75, 95% CI 0.64-0.89), and American Indians (RR 0.73, 95% CI 0.60-0.88). The summary effect for non-Hispanic Blacks (RR 0.91, 95% CI 0.76-1.08) was not significant. CONCLUSIONS: The results of the present study indicate that PA (comparing most to least active groups) provides significant protection from T2D, with the exception of non-Hispanic Blacks. The results also indicate a need for race-ethnicity-specific reporting of RRs in prospective cohort studies that incorporate multiethnic samples.

Effect of ActiGraph's low frequency extension for estimating steps and physical activity intensity.

This study examined the effects of the ActiGraph's (AG) low-frequency extension (LFE) filter on steps and physical activity classification in the free-living environment. Thirty-four African-American women (age, 24.5±5.2 years; BMI, 24.9±4.5 kg/m2) had daily activity measured simultaneously with an AG-GT3X+ accelerometer and a New Lifestyles NL-800 pedometer for seven days. Steps per day (steps/day) and time (minutes/day) spent in sedentary, light, and moderate-to-vigorous physical activity (MVPA) were examined with and without the LFE filter (AG-LFE and AG-N, respectively). The AG-LFE recorded more total steps (13,723±4,983 steps/day) compared to AG-N and NL-800 (6,172±2,838 and 5,817±3,037 steps/day, respectively; p<0.001). Compared to the AG-N, the AG-LFE estimated less time in sedentary behaviors (518.7±92.1 vs. 504.2±105.4 min/day, respectively; p<0.001), and more time in light (247.7±70.4 vs. 279.1±74.7 min/day, respectively; p<0.001) and MVPA (18.9±16.9 vs. 21.5±18.2 min/day, respectively; p<0.001), respectively. These data suggest that steps and physical activity classifications will be affected when using the ActiGraph with and without the LFE filter. Future research should investigate the accuracy of these measures using the LFE filter.

Potential Causes of Elevated REE after High-Intensity Exercise.

INTRODUCTION: Resting energy expenditure (REE) increases after an intense exercise; however, little is known concerning mechanisms. PURPOSE: The purpose of this study was to determine effects of a single bout of moderate-intensity continuous (MIC) aerobic exercise, or high-intensity interval (HII) exercise on REE under energy balance conditions. METHODS: Thirty-three untrained premenopausal women were evaluated at baseline, after 8-16 wk of training, 22 h after either MIC (50% peak V˙O2) or HII (84% peak V˙O2). Participants were in a room calorimeter during and after the exercise challenge. Food intake was adjusted to obtain energy balance across 23 h. REE was measured after 22 h after all conditions. Twenty-three-hour urine norepinephrine concentration and serum creatine kinase activity (CrKact) were obtained. Muscle biopsies were obtained in a subset of 15 participants to examine muscle mitochondrial state 2, 3, and 4 fat oxidation. RESULTS: REE was increased 22 h after MIC (64 ± 119 kcal) and HII (103 ± 137 kcal). Markers of muscle damage (CrKact) increased after HII (9.6 ± 25.5 U·L) and MIC (22.2 ± 22.8 U·L), whereas sympathetic tone (urine norepinephrine) increased after HII (1.1 ± 10.6 ng·mg). Uncoupled phosphorylation (states 2 and 4) fat oxidation were related to REE (r = 0.65 and r = 0.55, respectively); however, neither state 2 nor state 4 fat oxidation increased after MIC or HII. REE was not increased after 8 wk of aerobic training when exercise was restrained for 60 h. CONCLUSIONS: Under energy balance conditions, REE increased 22 h after both moderate-intensity and high-intensity exercise. Exercise-induced muscle damage/repair and increased sympathetic tone may contribute to increased REE, whereas uncoupled phosphorylation does not. These results suggest that moderate- to high-intensity exercise may be valuable for increasing energy expenditure for at least 22 h after the exercise.