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Exercise provides a robust physiological stimulus that evokes cross-talk among multiple tissues that when repeated regularly (i.e., training) improves physiological capacity, benefits numerous organ systems, and decreases the risk for premature mortality. However, a gap remains in identifying the detailed molecular signals induced by exercise that benefits health and prevents disease. The Molecular Transducers of Physical Activity Consortium (MoTrPAC) was established to address this gap and generate a molecular map of exercise. Preclinical and clinical studies will examine the systemic effects of endurance and resistance exercise across a range of ages and fitness levels by molecular probing of multiple tissues before and after acute and chronic exercise. From this multi-omic and bioinformatic analysis, a molecular map of exercise will be established. Altogether, MoTrPAC will provide a public database that is expected to enhance our understanding of the health benefits of exercise and to provide insight into how physical activity mitigates disease.

Background Exercise is recommended for weight management, yet exercise produces less weight loss than expected, which is called weight compensation. The mechanisms for weight compensation are unclear. Objective The aim of this study was to identify the mechanisms responsible for compensation. Methods In a randomized controlled trial conducted at an academic research center, adults (n = 198) with overweight or obesity were randomized for 24 wk to a no-exercise control group or 1 of 2 supervised exercise groups: 8 kcal/kg of body weight/wk (KKW) or 20 KKW. Outcome assessment occurred at weeks 0 and 24. Energy intake, activity, and resting metabolic rate (RMR) were measured with doubly labeled water (DLW; with and without adjustments for change in RMR), armband accelerometers, and indirect calorimetry, respectively. Appetite and compensatory health beliefs were measured by self-report. Results A per-protocol analysis included 171 participants (72.5% women; mean ± SD baseline body mass index: 31.5 ± 4.7 kg/m2). Significant (P < 0.01) compensation occurred in the 8 KKW (mean: 1.5 kg; 95% CI: 0.9, 2.2 kg) and 20 KKW (mean: 2.7 kg; 95% CI: 2.0, 3.5 kg) groups, and compensation differed significantly between the exercise groups (P = 0.01). Energy intake by adjusted DLW increased significantly (P < 0.05) in the 8 KKW (mean: 90.7 kcal/d; 95% CI: 35.1, 146.4 kcal/d) and 20 KKW (mean: 123.6 kcal/d; 95% CI: 64.5, 182.7 kcal/d) groups compared with control (mean: −2.3 kcal/d; 95% CI: −58.0, 53.5 kcal/d). Results were similar without DLW adjustment. RMR and physical activity (excluding structured exercise) did not differentially change among the 3 groups. Participants with higher compared with lower compensation reported increased appetite ratings and beliefs that healthy behaviors can compensate for unhealthy behaviors. Furthermore, they increased craving for sweet foods, increased sleep disturbance, and had worsening bodily pain. Conclusions Compensation resulted from increased energy intake and concomitant increases in appetite, which can be treated with dietary or pharmacological interventions. Compensation was not due to activity or metabolic changes. This trial was registered at clinicaltrials.gov as NCT01264406.

Greater blood concentrations of nonesterified fatty acids (NEFA) and lesser blood concentrations of glucose are indicative of the normal process of nutrient partitioning that occurs in early postpartum dairy cows. The objective was to determine the relationship between blood NEFA and glucose concentrations and subsequent conception at first insemination in postpartum dairy cows. Holstein (n=148) and Guernsey (n=8) dairy cows were blood sampled at approximately d 10, 7, and 3 prepartum, on the day of calving and 3, 7, 14, and 21 d postpartum for measurement of NEFA and glucose concentrations. Serum and plasma were harvested and used for measurement of NEFA and glucose concentrations, respectively. Cows were given a presynchronization treatment (2 injections of PGF(2α) 14 d apart) with the second PGF(2α) injection occurring 14 d before the initiation of the timed AI (TAI) protocol. Blood for determination of progesterone concentrations was collected at each presynchronization injection and at the initiation of the TAI protocol that was used for first insemination (74±7 d postpartum). Cows were considered noncycling if serum progesterone concentrations at the 2 presynchronization PGF(2α) injections (d 37 and 51±7 postpartum) and at the initiation of the TAI protocol (d 65±7 postpartum) were ≤1 ng/mL, and there was no indication of ovulation or presence of a corpus luteum by ultrasound examination at the initiation of the TAI protocol. Pregnancy was determined at 33 d and again at 61 d after first insemination by using ultrasound. Across all days, serum NEFA and plasma glucose concentrations were not different between cows that ovulated before the initiation of the TAI program (cycling) compared with those that did not ovulate (noncycling). Serum NEFA concentrations, however, were less and plasma glucose concentrations were greater during the early postpartum period for cows that subsequently became pregnant at first insemination compared with those that failed to become pregnant. Logistic regressions were used to predict the probability of pregnancy based on NEFA and glucose concentrations from individual days. The prediction with the greatest likelihood ratio was for d 3 postpartum NEFA and glucose concentrations. Nutritional status during the early postpartum period (within 1 wk after calving), as indicated by blood NEFA and glucose concentrations, may affect subsequent fertility by a mechanism that is independent from interval to first ovulation.

OBJECTIVETo establish whether exercise improves quality of life (QOL) in individuals with type 2 diabetes and which exercise modalities are involved.RESEARCH DESIGN AND METHODSHealth Benefits of Aerobic and Resistance Training in individuals with type 2 Diabetes (HART-D; n = 262) was a 9-month exercise study comparing the effects of aerobic training, resistance training, or a combination of resistance and aerobic training versus a nonexercise control group on hemoglobin A1c (HbA1c) in sedentary individuals with type 2 diabetes. This study is an ancillary analysis that examined changes in QOL after exercise training using the Short Form-36 Health Survey questionnaire compared across treatment groups and with U.S. national norms.RESULTSThe ancillary sample (n = 173) had high baseline QOL compared with U.S. national norms. The QOL physical component subscale (PCS) and the general health (GH) subscale were improved by all three exercise training conditions compared with the control group condition (resistance: PCS, P = 0.005; GH, P = 0.003; aerobic: PCS, P = 0.001; GH, P = 0.024; combined: PCS, P = 0.015; GH, P = 0.024). The resistance training group had the most beneficial changes in bodily pain (P = 0.026), whereas physical functioning was most improved in the aerobic and combined condition groups (P = 0.025 and P = 0.03, respectively). The changes in the mental component score did not differ between the control group and any of the exercise groups (all P > 0.05). The combined training condition group had greater gains than the aerobic training condition group in the mental component score (P = 0.004), vitality (P = 0.031), and mental health (P = 0.008) and greater gains in vitality compared with the control group (P = 0.021).CONCLUSIONSExercise improves QOL in individuals with type 2 diabetes. Combined aerobic/resistance exercise produces greater benefit in some QOL domains.