High-intensity high-volume swimming induces more robust signaling through PGC-1α and AMPK activation than sprint interval swimming in <i>m. triceps brachii</i>

We aimed to test whether high-intensity high-volume training (HIHVT) swimming would induce more robust signaling than sprint interval training (SIT) swimming within the m. triceps brachii due to lower metabolic and oxidation. Nine well-trained swimmers performed the two training procedures on separate randomized days. Muscle biopsies from m. triceps brachii and blood samples were collected at three different time points: a) before the intervention (pre), b) immediately after the swimming procedures (post) and c) after 3 h of rest (3 h). Hydroperoxides, creatine kinase (CK), and lactate dehydrogenase (LDH) were quantified from blood samples, and peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) and the AMPKpTHR172/AMPK ratio were quantified by Western blot analysis. PGC-1α, sirtuin 3 (SIRT3), superoxide-dismutase 2 (SOD2), and vascular endothelial growth factor (VEGF) mRNA levels were also quantified. SIT induced a higher release of LDH (

Soil remediation approach and bacterial community structure in a long-term contaminated soil by a mining spill (Aznalcóllar, Spain)

The Aznalcóllar accident, which occurred in 1998, spilled 36 × 10 m of pyritic sludge and 9 × 10 m of acidic water around an area of 43 km in the south of Spain. This spill is considered one of the most important metal-mining associated accidents worldwide. In this study, two soil remediation techniques were evaluated: the addition of marble sludge (liming treatment, LS) and the mixing of recovered soils (RC) with contaminated soils (CT) (biopile treatment, BS). Both LS and BS significantly reduce the solubility of Cu, Zn, As, and Pb mainly due to the increase in pH and organic matter content, respectively. Soil basal respiration rate and the seed germination and root elongation bioassay with Lactuca sativa were used to evaluate the toxicity of the potential pollution in the sampled soils. Both bioassays showed that the CT soils exhibited the highest toxicity with a significant reduction in the toxicity of the amended soils (LS and BS). The abundance and structure of microbial communities in the soils were determined by qPCR and Illumina 16S rRNA sequencing, respectively. The absolute abundances of total bacterial and archaeal populations, ammonium oxidising bacteria, and denitrifiers in the CT soils were statistically lower than these found in the other three soils. Similarly, the structure of the bacterial community was highly different in the CT soils. Our results underline the persistence of the detrimental effect of pollutants in CT soils compared to the recuperated (RC) and amended soils (LS and BS). We also highlight the uses of liming or biopile as remediation techniques as satisfactory tools to reduce the impact of heavy metals in the contaminated Aznalcóllar soils.This work was supported by the Research Project RTI 2018-094327-B-I00 (Ministry of Science, Innovation and Universities)

Influence of physical fitness and weight status on autonomic cardiac modulation in children

Background: This study provides reference values for cardiovascular modulation at rest, during maximal exercise test and recovery after exercise in Caucasian children according to weight status and cardiorespiratory fitness (CRF) level. Additionally, the current study analyzed several correlations between autonomic cardiovascular modulation, cardiorespiratory performance and cardiometabolic risk. The principal goal of this study was to analyze cardiac function at rest, during maximum exercise, and during the recovery phase in children grouped according to weight status and CRF level. Methods: One hundred and fifty-two healthy children (78 girls) 10–16 years of age were divided into three groups: soccer and basketball players (SBG), endurance group (EG), and sedentary people with overweight and obesity (OOG). A cardiac RR interval monitor recorded the cardiac data and specific software analyzed the cardiac autonomic response through heart rate (HR) and HR variability. The study analyzed resting HR (RHR), HRpeak, and HR recovery (HRR). Results: OOG showed significant poorer performance in the Léger test lower V̇O 2 max and higher values of blood pressure at rest and post-exercise than sport groups. The EG presented the best results in CRF and cardiometabolic risk (CMR) in relation to SBG and OOG. The OOG showed higher percentage of HR values, compatible with an unhealthy cardiovascular autonomic modulation than the sport groups, with significant differences in bradycardia, HR reserve, and HRR 5 min. Conclusions: Aerobic performance, vagal activity, blood pressure, chronotropic competence, and HRR have significant associations with CMR parameters. Impact: The current study presents reference values of autonomic cardiac function in Caucasian children according to weight status and cardiorespiratory fitness level.Aerobic performance, vagal activity, blood pressure, chronotropic competence, and heart rate during the recovery period after exercise have significant associations with cardiometabolic risk parameters.Children with overweight and obesity show signs of autonomic dysfunction reflected as low cardiac vagal activity and poor chronotropic competence

Molecular signaling in response to swimming.

<p>The ratio of AMPK phosphorylation at Thr172/total AMPK increased at post in response to SIT and at 3h in response to HIHVT (A). The PGC-1α mRNA levels increased at post in response to SIT and at 3 h in response to both SIT and HIHVT (B). Content of PGC-1α protein increased in response to HIHVT at 3 h (C). SIRT1 remains unchanged throughout all the time points examined (D). Results are shown as mean ± SEM. The graph shows a representative crop blot. * <i>p</i> < 0.05 ** <i>p</i> < 0.01 *** <i>p</i> < 0.001 <i>vs</i>. pre. ‡ <i>p</i> < 0.05 <i>vs</i>. SIT.</p

SIRT3 and SOD2 transcription.

<p>The SIRT3 mRNA levels were unchanged at all the time points and swimming intensities examined (A). SOD2 mRNA levels decreased at post in response to HIHVT (B). Results are shown as mean ± SEM. * p < 0.05 <i>vs</i>. pre.</p

Subject characteristics.

<p>Subject characteristics.</p