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BACKGROUND & AIMS: Maximal VO2 (VO2max) and metabolic equivalents (METs) decline with aging due to body composition and cardiovascular modifications. However, a detailed evaluation of these variables for this population has not been done. The aim of this study was to evaluate VO2max and METs in healthy elderly women, and to establish whether the calculated resting VO2 (3.5 ml/min/kg) underestimates the true METs. METHODS: 81 females over 65 years old attending a twice-weekly mild fitness program were studied. Body composition was measured by DEXA. VO2max and resting VO2 (VO(2rest-meas)) were measured by indirect calorimetry. METs were measured (METs-meas) using the VO2max/VO(2rest-meas) ratio, and calculated (METs-cal) from the ratio between measured VO2max and calculated resting VO2 (3.5 ml/min/kg of body weight). RESULTS: The VO(2rest-meas) and VO2max measured by indirect calorimetry were 2.9+/-0.4 ml/min/kg and 17.5+/-2.8 ml/min/kg, respectively. The METs-meas were higher than the METs-cal (6.1+/-1.2 vs 5.0+/-0.8; p<0.001). The 25th-75th percentile range of measured METs was 5.2-6.8. CONCLUSIONS: Our study confirmed that, in elderly women, METs values ranging between 5 and 7 are compatible with an acceptable physical activity. The estimated resting VO2 (3.5 ml/min/kg) does not appear to be applicable to elderly women, because it underestimates the real METs in this population. [ABSTRACT FROM AUTHOR]

Minimization of excess sludge produced by wastewater treatment plants has become a topical theme nowadays. One of the most used approaches to achieve this aim is the anaerobic side-stream reactor (ASSR) process. This is considered affected by the hydraulic retention time (HRT) of the anaerobic reactor, the anaerobic sludge loading rate (ASLR) and the sludge interchange ratio (SIR), although, studies available in the literature did not reflect a clear relationship with the sludge minimization yields. To overcome this, a novel parameter namely anaerobic exposure time (AET) was defined and related to reduction of the observed yield coefficient (Y obs ) in a lab-scale plant implementing the ASSR process. Furthermore, the AET was validated by performing a detailed and thorough review of previous literature. Excess sludge production was successfully reduced (10-60 %) with the increase of the AET (7.9-13 h/d), although maintaining the same HRT in the ASSR and a constant sludge interchange ratio (SIR) (100 %). A strong correlation (Pearson = 0.763) was found between the AET, and the Y obs reduction reported in previous studies, also indicating a linear relationship (R 2 = 0.92) between these parameters. Contrarily, the correlation between the Y obs with the ASLR and the ASSR-HRT resulted moderate (Pearson = 0.186) or weak (Pearson=-0.346), respectively. Overall, while operating at low AET (< 6 h), maintenance and uncoupling metabolism were found the main sludge reduction mechanisms. Increasing the AET (>8 h) favoured the occurrence of extracellular polymeric substances (EPS) hydrolysis and endogenous decay mechanisms, which improved excess sludge reduction. To conclude, the AET could be considered a reliable parameter to be used for design or control purposes for the ASSR-based process., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Study Objective: Our study investigates nutritional status, resting energy expenditure (REE) and physical performance in elderly patients with stable COPD to identify any early conditions of hypermetabolism, malnutrition and sarcopenia., Methods: Eighty-six males (40 stable COPD and 46 healthy subjects) over 65 years old were studied. All subjects underwent spirometry, blood gas analysis and a 6-min walking test (6MWT). Fat-free mass (FFM) and appendicular skeletal muscle mass (ASMM) were measured by dual energy X-ray absorptiometry (DEXA). REE was measured by indirect calorimetry., Results: COPD patients had a lower FFM both expressed in kilograms and after correction for height squared. The prevalence of sarcopenia was higher for COPD subjects (38% vs 31%). REE, both in absolute values and adjusted for FFM was significantly higher in COPD patients. Hypermetabolism was found in 60% of COPD cases and 13.7% (P<0.01) of healthy subjects. No relationship was found in COPD patients between the measured/predicted REE ratio (REE(m)/REE(p)) and FEV1. In the hypermetabolic COPD subgroup, the REE(m)/REE(p) ratio correlated with 6MWT., Conclusions: Elderly patients with stable COPD develop an increased REE. This hypermetabolism seems to be independent of the severity of the pulmonary obstruction and to influence the patient's physical performance.