Resistance Exercise Program in Cognitively Normal Older Adults: CERT-Based Exercise Protocol of the AGUEDA Randomized Controlled Trial.

OBJECTIVES: To provide a comprehensive CERT (Consensus on Exercise Reporting Template)-based description of the resistance exercise program implemented in the AGUEDA (Active Gains in brain Using Exercise During Aging) study, a randomized controlled trial investigating the effects of a 24-week supervised resistance exercise program on executive function and related brain structure and function in cognitively normal older adults. DESIGN AND PARTICIPANTS: 90 cognitively normal older adults aged 65 to 80 were randomized (1:1) to a: 1) resistance exercise group; or a 2) wait-list control group. Participants in the exercise group (n = 46) performed 180 min/week of resistance exercise (3 supervised sessions per week, 60 min/session) for 24 weeks. INTERVENTION: The exercise program consisted of a combination of upper and lower limb exercises using elastic bands and the participant's own body weight as the main resistance. The load and intensity were based on the resistance of the elastic bands (7 resistances), number of repetitions (individualized), motor complexity of exercises (3 levels), sets and rest (3 sets/60 sec rest), execution time (40-60 sec) and velocity (as fast as possible). SETTINGS: The maximum prescribed-target intensity was 70-80% of the participants' maximum rate of perceived exertion (7-8 RPE). Heart rate, sleep quality and feeling scale were recorded during all exercise sessions. Those in the wait-list control group (n = 44) were asked to maintain their usual lifestyle. The feasibility of AGUEDA project was evaluated by retention, adherence, adverse events and cost estimation on the exercise program. RESULTS AND CONCLUSIONS: This study details the exercise program of the AGUEDA trial, including well-described multi-language manuals and videos, which can be used by public health professionals, or general public who wish to implement a feasible and low-cost resistance exercise program. The AGUEDA exercise program seems to be feasible by the high retention (95.6%) and attendance rate (85.7%), very low serious adverse event (1%) and low economic cost (144.23 € /participant/24 weeks). We predict that a 24-week resistance exercise program will have positive effects on brain health in cognitively normal older adults.

Effectiveness of an intervention to reduce sedentary behaviour as a personalised secondary prevention strategy for patients with coronary artery disease: main outcomes of the SIT LESS randomised clinical trial.

BACKGROUND: A high sedentary time is associated with increased mortality risk. Previous studies indicate that replacement of sedentary time with light- and moderate-to-vigorous physical activity attenuates the risk for adverse outcomes and improves cardiovascular risk factors. Patients with cardiovascular disease are more sedentary compared to the general population, while daily time spent sedentary remains high following contemporary cardiac rehabilitation programmes. This clinical trial investigated the effectiveness of a sedentary behaviour intervention as a personalised secondary prevention strategy (SIT LESS) on changes in sedentary time among patients with coronary artery disease participating in cardiac rehabilitation. METHODS: Patients were randomised to usual care (n = 104) or SIT LESS (n = 108). Both groups received a comprehensive 12-week centre-based cardiac rehabilitation programme with face-to-face consultations and supervised exercise sessions, whereas SIT LESS participants additionally received a 12-week, nurse-delivered, hybrid behaviour change intervention in combination with a pocket-worn activity tracker connected to a smartphone application to continuously monitor sedentary time. Primary outcome was the change in device-based sedentary time between pre- to post-rehabilitation. Changes in sedentary time characteristics (prevalence of prolonged sedentary bouts and proportion of patients with sedentary time ≥ 9.5 h/day); time spent in light-intensity and moderate-to-vigorous physical activity; step count; quality of life; competencies for self-management; and cardiovascular risk score were assessed as secondary outcomes. RESULTS: Patients (77% male) were 63 ± 10 years and primarily diagnosed with myocardial infarction (78%). Sedentary time decreased in SIT LESS (- 1.6 [- 2.1 to - 1.1] hours/day) and controls (- 1.2 [ ─1.7 to - 0.8]), but between group differences did not reach statistical significance (─0.4 [─1.0 to 0.3]) hours/day). The post-rehabilitation proportion of patients with a sedentary time above the upper limit of normal (≥ 9.5 h/day) was significantly lower in SIT LESS versus controls (48% versus 72%, baseline-adjusted odds-ratio 0.4 (0.2-0.8)). No differences were observed in the other predefined secondary outcomes. CONCLUSIONS: Among patients with coronary artery disease participating in cardiac rehabilitation, SIT LESS did not induce significantly greater reductions in sedentary time compared to controls, but delivery was feasible and a reduced odds of a sedentary time ≥ 9.5 h/day was observed. TRIAL REGISTRATION: Netherlands Trial Register: NL9263. Outcomes of the SIT LESS trial: changes in device-based sedentary time from pre-to post-cardiac rehabilitation (control group) and cardiac rehabilitation + SIT LESS (intervention group). SIT LESS reduced the odds of patients having a sedentary time >9.5 hours/day (upper limit of normal), although the absolute decrease in sedentary time did not significantly differ from controls. SIT LESS appears to be feasible, acceptable and potentially beneficial, but a larger cluster randomised trial is warranted to provide a more accurate estimate of its effects on sedentary time and clinical outcomes. CR: cardiac rehabilitation.

Impact of COVID-19 lockdown on physical activity and sedentary behaviour in Dutch cardiovascular disease patients.

BACKGROUND: Coronavirus disease 2019 (COVID-19) lockdown restrictions may impact lifestyle and therefore also physical (in)activity patterns in patients with cardiovascular disease (CVD). This study aimed to evaluate the effect of lockdown on physical activity and sedentary behaviour. METHODS: A total of 1565 Dutch CVD patients participated in this prospective cohort study, in which we compared physical activity and sedentary behaviour before and during the COVID-19 lockdown period. Baseline measures were assessed in 2018 and data on follow-up measures were collected between 17 and 24 April 2020 (5 weeks after the introduction of COVID-19 lockdown restrictions). Validated questionnaires were used to assess physical activity and sedentary behaviour. RESULTS: Moderate-to-vigorous physical activities increased from 1.6 (0.9, 2.8) to 2.0 (1.0, 3.5) h/day [median (interquartile range)] (p < 0.001) during the COVID-19 lockdown, mainly due to an increase in time spent walking and doing odd jobs. In contrast, time spent exercising significantly declined [1.0 (0.0, 2.3) to 0.0 (0.0, 0.6) h/week], whereas sedentary time increased from 7.8 (6.1, 10.4) to 8.9 (6.8, 11.4) h/day (p < 0.001). The absolute increase in physical activity was 13 (-36, 81) min/day, whereas sedentary behaviour increased by 55 (-72, 186) min/day. CONCLUSION: Despite a small increase in physical activities, the larger increase in sedentary time induced a net reduction in habitual physical activity levels in Dutch CVD patients during the first-wave COVID-19 lockdown. Since a more inactive lifestyle is strongly associated with disease progression and mortality, we encourage CVD patients and their caregivers to explore novel solutions to increase physical activity levels and reduce sedentary time during (and beyond) the COVID-19 pandemic.

On-line NIR analysis of fat, water and protein in industrial scale ground meat batches.

Fat, water and protein contents in industrial scale meat batches were determined on-line by near infrared (NIR) reflectance spectroscopy. The NIR instrument was mounted at the outlet of a large meat grinder, and the measurements were performed in an industrial environment. Beef and pork samples, with chemical compositions of 7-26% fat, 58-75% water and 15-21% protein, were processed with hole diameters of 13mm in the grinder plate. Calibrations were made both for a combined set of beef and pork samples, and for separate sets of beef and pork samples. Validations were either done by full cross validation of the calibration set, or by bias corrected prediction of a test set. Prediction errors for the two sample sets, expressed as root mean square errors of cross validation or standard error of prediction, were in the ranges 0.82-1.49% fat, 0.94-1.33% water and 0.35-0.70% protein, depending of sample set and species of animal. The presented application is an improvement to the existing manual meat standardisation procedure, and has been implemented for regular use in a Norwegian meat manufacturing plant.

Dynorphin-(1-13) is a potent in vivo suppressor of vasopressin levels in the rat.

Intracerebroventricular administration of dynorphin-(1-13) inhibits dose-dependently plasma vasopressin level in normal as well as in water-deprived rats, whereas systemic (subcutaneous) administration of this opioid peptide is ineffective in this respect. Simultaneous subcutaneous, but not intracerebroventricular, administration of naloxone prevents the suppressive effect of dynorphin-(1-13) on plasma vasopressin levels.

Characterization of the alpha-MSH-like immunoreactivity in blood and cerebrospinal fluid of the rat.

We have investigated the nature of the alpha-melanocyte stimulating hormone-like immunoreactivity (alpha-MSH-LI) in blood and cerebrospinal fluid (CSF) of the rat. Blood and CSF from intact animals were subjected to high pressure liquid chromatography (HPLC) followed by a radioimmunoassay (RIA) specific for the C-terminal part of the alpha-MSH molecule. It appeared that in both body fluids the predominant alpha-MSH-LI co-migrated with synthetic alpha-MSH and not with its des-acetyl or di-acetyl analogues. We conclude that alpha-MSH is the predominant form of alpha-MSH-LI circulating in plasma and CSF of rats from our Wistar strain.

The effect of gamma-type endorphins on alpha-MSH release in the rat.

Neuroleptic drugs increase the level of alpha-melanotropin (alpha-MSH) in the blood of the rat. We have investigated whether neuroleptic-like peptides, the gamma-type endorphins, also affect alpha-MSH release. A structure-activity study revealed that (des-enkephalin)-gamma-endorphin (DE gamma E, beta-LPH-(66-77), beta-endorphin-(6-17)) is able to increase plasma alpha-MSH levels after intracerebroventricular injection, while the longer gamma-type endorphins, i.e. gamma E (beta-LPH-(61-77)), beta-endorphin-(1-17)), and DT gamma E (beta-LPH-(62-77), beta-endorphin-(2-17)) were without effect in the dosage used. A dose-response study revealed a more or less bell-shaped relationship for the effect of DE gamma E on plasma alpha-MSH levels. The effect of DE gamma E could not be counteracted by apomorphine or naloxone. The observations indicate that DE gamma E increases plasma alpha-MSH levels in a way distinct from that of haloperidol and the opiate peptide beta-endorphin. On the other hand, a time-course of plasma alpha-MSH levels after DE gamma E administration resembled the one which has been seen after haloperidol injection. From experiments performed on pituitary neurointermediate lobes incubated in vitro, it seems not likely that DE gamma E acts directly on the dopamine receptors of the pituitary in affecting alpha-MSH release. In conclusion, it appears that DE gamma E affects alpha-MSH levels in plasma in a way distinct from that of the neuroleptic drug haloperidol and of the opiate-peptide beta-endorphin.

Changes in cerebrospinal fluid levels of vasopressin and oxytocin of the rat during various light-dark regimes.

Levels of arginine-vasopressin (AVP) and oxytocin (OXT) in cerebrospinal fluid (CSF) of rats were determined at various times of the day and the night under normal and changed light-dark conditions. During a regular daily 14 h light and 10 h dark cycle (lights on 06.00 h, off 20.00 h), AVP in CSF reached a peak at 13.00 h, while the lowest levels were found at 19.00 h. Reversal of the normal light-dark cycle into a 14 h dark and 10 h light cycle (lights on 20.00 h, off 06.00 h) did not change the normal AVP rhythm. These lighting conditions elevated the OXT levels in the CSF as compared to those found during a normal light-dark regime, but again no differences were observed between the OXT levels determined at the various time-points. A shift of 6 h of the light-dark cycle (lights on 12.00 h, lights off 02.00 h), completely disrupted the AVP rhythm. However, after 3 weeks of adaptation to this new light-dark regime a high level of AVP in CSF was again observed at 13.00 h, and a low level at 19.00 h. The present data suggest that changes in the normal light-dark conditions affect the levels of neurohypophyseal peptides in the CSF. The results are of interest because of reported changes in memory function induced by alterations in the light-dark cycle.

Differential effects of various stimuli on AVP levels in blood and cerebrospinal fluid.

Water deprivation, drinking water containing 2% NaCl, or systemic injection with histamine or nicotine markedly increased plasma levels of vasopressin in rats. In contrast, none of the applied stimuli changed vasopressin levels in the CSF collected simultaneously from the same animal. These data suggest that the blood levels of vasopressin are controlled quite differently from CSF levels of this hormone.