Health-Related Data from a Community Risk Reduction Program: Healthy U™ of DelMarva

The primary aim of this study was to examine baseline data from participants in a community coalition aiming to reduce disease risk and enhance lifestyle modification. Adults (N = 5,876) residing in the Eastern Shore of Maryland enrolled in the program, and were encouraged to re-enroll the following year. Incentives were offered to enhance participation and program adherence. Cooking demonstrations, exercise classes, and lectures were held, and community-wide messages espousing healthy behavior were spread to increase knowledge of healthy behavior. Participants filled out a survey, and body mass index (BMI) and waist-to-hip ratio (WHR) were measured. Frequency statistics were used to analyze data. BMI (29.73 ± 7.38 kg/m2 ), waist circumference (37.15 ± 6.85 in.), and WHR (0.84 ± 0.09) surpassed healthy values. Intake of fruits and vegetables was low, inactivity was high (50% of members exercised less than two days/week), and diets moderate or high in fat were prevalent (70% of participants). Data confirm the rather unhealthy lifestyle of our local population. Future interventions to enhance wellness and reduce disease in this population are warranted

Ellipsoidal classification via semidefinite programming

We propose a classification approach exploiting relationships between ellipsoidal separation and Support-vector Machine (SVM) with quadratic kernel. By adding a (Semidefinite Programming) SDP constraint to SVM model we ensure that the chosen hyperplane in feature space represents a non-degenerate ellipsoid in input space. This allows us to exploit SDP techniques within Support-vector Regression (SVR) approaches, yielding better results in case ellipsoid-shaped separators are appropriate for classification tasks. We compare our approach with spherical separation and SVM on some classification problems

Continuous Leg Cycling Ergometry Prescribed at Identical Relative Power Output Elicits Different Physiological Responses Versus Arm Cycle Ergometry

PURPOSE: The aim of this study was to compare physiological and perceptual responses to progressive moderate intensity continuous exercise (MICE) between leg (LCE) and arm cycle ergometry (ACE). METHODS: Seventeen active men and women (age and percent body fat = 26 ± 7 yr and 18 ± 3 %) initially performed graded exercise on each modality to assess maximal oxygen uptake (VO2max) and peak power output (PPO). Using a randomized crossover design, they subsequently performed 45 min of MICE consisting of three 15 min bouts at 20, 40, and 60 % PPO on each modality. Gas exchange data (VO2, VCO2, VE, and respiratory exchange ratio (RER), heart rate (HR), blood lactate concentration (BLa), affective valence, and rating of perceived exertion (RPE) were acquired during each bout. RESULTS: Compared to ACE, LCE revealed significantly higher (p \u3c 0.05) peak (94 ± 6 vs. 88 ± 9 %HRmax, d = 0.81) and mean HR (73 ± 6 vs. 66 ± 6 %HRmax, d = 1.20) and VO2 (54 ± 5 vs. 50 ± 7 %VO2max, d = 0.68). Time spent above 70 (22 ± 7 vs. 15 ± 8 min, d = 1.03) and 80 %HRmax (15 ± 6 vs. 9 ± 6 min, d = 1.04) was significantly greater with LCE versus ACE. LCE revealed significantly higher BLa versus ACE (5.5 ± 2.0 vs. 4.7 ± 1.5 mM, d = 0.48). CONCLUSIONS: These results exhibit that progressive leg cycling at identical intensities elicits a greater cardiometabolic stimulus than arm ergometry. Moreover, leg cycling leads to greater duration spent at intensities between 70 – 89 %VO2max which may have application to selecting specific exercise modes when prescribing MICE to increase cardiorespiratory fitness. Lastly, use of %PPO led to participants being classified in different intensity domains which merits prescribing MICE according to various threshold measures rather than relative intensities acquired from incremental exercise

Identifying Maximal Fat Oxidation during Arm Ergometry

Metabolic responses have been extensively studied in response to various exercise modalities, such as treadmill running and cycling. Achten et al. (2002) demonstrated that graded exercise testing in trained cyclists using 3 minute (min) stages led to similar estimates of fat oxidation (FOx) and maximal fat oxidation (MFO) as 5 min stages. However, minimal research has studied FOx responses during exercises using arm cycle ergometry (ACE). PURPOSE: To compare FOx responses during progressive ACE using 3 and 5 min stages. METHODS: Participants consisted of 11 healthy, non-obese men and women (age = 24±9 yr, %BF = 23±5%, VO2peak and PPO = 23.5±5.7 ml/kg/min and 103.2±40.4 W) who are physically active (PA = 5±2 h/wk) but unfamiliar with ACE. Participants initially underwent graded exercise testing to determine peak oxygen uptake (VO2peak) and peak power output (PPO) on the ACE. Utilizing a randomized crossover design, on two separate days, following a 12 h fast, participants performed progressive exercise on the ACE with gradually increasing intensities every 3 or 5 min, starting at 15%PPO and PO increasing by 10% per stage. Gas exchange data, heart rate (HR), and blood lactate concentration (BLa) were obtained throughout exercise. RESULTS: Paired t-test showed no significant differences in MFO between 3 and 5 min stages (0.16±0.07 vs 0.13±0.07 g/min, p=0.07), and there was a strong, positive correlation between these values (r=0.82, p =0.002). There were no significant differences between protocols in BLa at MFO (1.94 ±1.0 vs. 1.95±0.8 mM, p= 0.93), MFO expressed as percent of peak HR (%HRpeak) (59±9 vs. 58±11 %HRpeak, p= 0.80), % VO2peak (38±8 vs. 42±15% VO2peak, p= 0.24) or power output (PO) at MFO (26±12 vs. 24±10 %PPO, p= 0.17). However, RER at MFO was significantly different between 3 and 5 min stages (0.83±0.05 vs. 0.86±0.03, p= 0.04). Results showed no significant duration X time interaction for BLa (p= 0.25), FOx (p= 0.44), carbohydrate oxidation (CHOOx) (p= 0.057), RER (p= 0.61), or blood glucose (p= 0.24) between stage durations. CONCLUSION: As no significant differences in FOx were revealed between stage durations, we recommend 3 min stages to identify metabolic responses during progressive ACE. However, more study is merited to elucidate the individual variability in the FOx response to exercise

Comparing Physiological Responses During Rowing High Intensity Interval Training (HIIT) versus High Intensity Functional Training (HIFT)

High intensity interval training (HIIT) improves cardiorespiratory fitness, glycemic control, and body composition, yet the majority of studies used cycling which employs a smaller muscle mass. Less data have examined the acute response to whole-body HIIT. PURPOSE: To compare physiological responses between HIIT rowing and high intensity functional training (HIFT). METHODS: Healthy, non-obese men and women (N=18, age=25±8 yr) who are physically active (PA=7±2hr, VO2max=39±8mL/kg/min) underwent graded exercise testing to determine VO₂max and peak power output (PPO) on the rowing ergometer. On two separate days, subjects performed a time-matched bout of HIFT or HIIT rowing. HIIFT required 6 ‘all-out’ sets of 10 push-ups, 10 jump squats, 20 mountain climbers, and 20 body-weight squats separated by 75 s recovery. HIIT rowing consisted of six 1min bouts at 85% PPO with 75 s of recovery. Gas exchange data, heart rate (HR), affective valence, and RPE were obtained during exercise. Blood lactate concentration (BLa) was measured at rest, bout 3, and 5, 10, and 15 min post-exercise. RESULTS: There were significant differences (p2 was higher (p=0.03) with HIIT rowing versus HIFT (1.88 ± 0.51 vs. 1.67 ± 0.35 L/min) as was total O2 (31±8 vs. 28±6L). GroupXtime interactions (pE, and RPE occurred, with higher values demonstrated to HIFT. CONCLUSION: HIFT elicited a higher peak HR, BLa, and RER, suggesting a higher peak cardiovascular stimulus and greater activation of glycolysis, likely due to greater recruitment of fast twitch fibers. Yet, HIIT rowing elicited higher energy expenditure and mean VO2 versus HIFT. The eccentric nature of HIFT may explain the blunted VO2 response, although more studies are needed to verify this result

Potts model on recursive lattices: some new exact results

We compute the partition function of the Potts model with arbitrary values of $q$ and temperature on some strip lattices. We consider strips of width $L_y=2$, for three different lattices: square, diced and `shortest-path' (to be defined in the text). We also get the exact solution for strips of the Kagome lattice for widths $L_y=2,3,4,5$. As further examples we consider two lattices with different type of regular symmetry: a strip with alternating layers of width $L_y=3$ and $L_y=m+2$, and a strip with variable width. Finally we make some remarks on the Fisher zeros for the Kagome lattice and their large q-limit.Comment: 17 pages, 19 figures. v2 typos corrected, title changed and references, acknowledgements and two further original examples added. v3 one further example added. v4 final versio

Verification Testing To Confirm VO2max Attainment in Inactive Women With Obesity

International Journal of Exercise Science 13(4): 1448-1458, 2020. Incidence of obesity is increasing worldwide which is deleterious to health due to its association with increased risk of cardiovascular disease, diabetes, and some cancers. Completion of regular physical activity in individuals with obesity increases maximal oxygen uptake (VO2max). However, whether individuals with obesity can exhibit ‘true’ VO2max is unresolved. This study examined efficacy of verification testing (VER) to identify ‘true’ VO2max in 17 inactive women with obesity (age, body fat, and VO2max = 37 ± 10 yr, 48.7 ± 3.5 %, and 19.4 ± 3.0 mL/kg/min, respectively). They performed ramp exercise (RAMP) to volitional fatigue followed by VER at 105 percent peak power output (%PPO) at baseline and after 3 and 6 wk of high intensity interval training. Results showed no difference in ramp and verification-derived VO2max (1.99 ± 0.37 L/min vs. 1.98 ± 0.32 L/min, 2.00 ± 0.40 L/min vs. 2.04 ± 0.38 L/min, and 2.08 ± 0.34 L/min vs. 2.08 ± 0.32 L/min at 0, 3 and 6 wk of training), although in 40 % of VER tests, VO2max was greater than the RAMP value. Overall, verification testing may be adopted as an additional approach to confirm ‘true’ VO2max attainment in obese women as ramp exercise frequently underestimates VO2max in this population

Burpee interval training is associated with a more favorable affective valence and psychological response than traditional high intensity exercise

Acute psychological responses to physical activity may help explain long-term adherence to it. Thus, we compared acute psychological responses to different exercise protocols with identical durations. Eighteen moderately active young adults [Mage = 23, SD = 3 years; MVO2max (maximum oxygen consumption) = 42.8, SD = 4.3 mL kg1 min1 ; MBMI (body mass index) = 24, SD = 2 kg m2 ] completed three low-volume exercise sessions in a crossover research design: (a) sprint interval training (SIT), (b) burpee interval training (BIT) requiring 10 × 5 second efforts with 35 seconds of passive recovery, and (c) a single bout of vigorous intensity continuous training (VICT) requiring 6 minutes and 5 seconds of running at ∼85% of peak heart rate (HRpeak). We assessed participants’ ratings of perceived exertion (RPE), affective valence, enjoyment, intention, preference, and self-reported recovery and wellness before, during, and after each session. BIT was associated with significantly greater enjoyment, preference, and exercise intention (at 5 × week) than VICT (p ≤ .05). SIT elicited greater RPE (M = 5.38, SD = 2.00) than both BIT (M = 2.88, SD = 1.23) and VICT (M = 3.55, SD = 1.38) (p ≤ .05), and we observed a higher increase in RPE over time with SIT versus BIT (p = .019). For affective valence, SIT (M = 0.55, SD = 2.12) elicited a more aversive response than both BIT (M = 2.55, SD = 1.09) and VICT (M = 1.94, SD = 1.51) (p ≤ .05), and there was a higher increase in this aversive response to SIT over time (p < .05). Forty-eight-hour postexercise session muscle soreness was significantly lower with VICT than with BIT (p = .03). Overall, BIT was associated with more positive psychological responses than SIT and VICT

Is a verification phase useful for confirming maximal oxygen uptake in apparently healthy adults? A systematic review and meta-analysis

BackgroundThe 'verification phase' has emerged as a supplementary procedure to traditional maximal oxygen uptake (VO2max) criteria to confirm that the highest possible VO2 has been attained during a cardiopulmonary exercise test (CPET).ObjectiveTo compare the highest VO2 responses observed in different verification phase procedures with their preceding CPET for confirmation that VO2max was likely attained.MethodsMEDLINE (accessed through PubMed), Web of Science, SPORTDiscus, and Cochrane (accessed through Wiley) were searched for relevant studies that involved apparently healthy adults, VO2max determination by indirect calorimetry, and a CPET on a cycle ergometer or treadmill that incorporated an appended verification phase. RevMan 5.3 software was used to analyze the pooled effect of the CPET and verification phase on the highest mean VO2. Meta-analysis effect size calculations incorporated random-effects assumptions due to the diversity of experimental protocols employed. I2 was calculated to determine the heterogeneity of VO2 responses, and a funnel plot was used to check the risk of bias, within the mean VO2 responses from the primary studies. Subgroup analyses were used to test the moderator effects of sex, cardiorespiratory fitness, exercise modality, CPET protocol, and verification phase protocol.ResultsEighty studies were included in the systematic review (total sample of 1,680 participants; 473 women; age 19-68 yr.; VO2max 3.3 ± 1.4 L/min or 46.9 ± 12.1 mL·kg-1·min-1). The highest mean VO2 values attained in the CPET and verification phase were similar in the 54 studies that were meta-analyzed (mean difference = 0.03 [95% CI = -0.01 to 0.06] L/min, P = 0.15). Furthermore, the difference between the CPET and verification phase was not affected by any of the potential moderators such as verification phase intensity (P = 0.11), type of recovery utilized (P = 0.36), VO2max verification criterion adoption (P = 0.29), same or alternate day verification procedure (P = 0.21), verification-phase duration (P = 0.35), or even according to sex, cardiorespiratory fitness level, exercise modality, and CPET protocol (P = 0.18 to P = 0.71). The funnel plot indicated that there was no significant publication bias.ConclusionsThe verification phase seems a robust procedure to confirm that the highest possible VO2 has been attained during a ramp or continuous step-incremented CPET. However, given the high concordance between the highest mean VO2 achieved in the CPET and verification phase, findings from the current study would question its necessity in all testing circumstances.Prospero registration idCRD42019123540