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Abstract Background DNA methylation profiling may provide a more accurate measure of the smoking status than self-report and may be useful in guiding clinical interventions and forensic investigations. In the current study, blood DNA methylation profiles of nearly 800 Polish individuals were assayed using Illuminia EPIC and the inference of smoking from epigenetic data was explored. In addition, we focused on the role of the AHRR gene as a top marker for smoking and investigated its responsiveness to other lifestyle behaviors. Results We found > 450 significant CpGs associated with cigarette consumption, and overrepresented in various biological functions including cell communication, response to stress, blood vessel development, cell death, and atherosclerosis. The model consisting of cg05575921 in AHRR (p = 4.5 × 10–32) and three additional CpGs (cg09594361, cg21322436 in CNTNAP2 and cg09842685) was able to predict smoking status with a high accuracy of AUC = 0.8 in the test set. Importantly, a gradual increase in the probability of smoking was observed, starting from occasional smokers to regular heavy smokers. Furthermore, former smokers displayed the intermediate DNA methylation profiles compared to current and never smokers, and thus our results indicate the potential reversibility of DNA methylation after smoking cessation. The AHRR played a key role in a predictive analysis, explaining 21.5% of the variation in smoking. In addition, the AHRR methylation was analyzed for association with other modifiable lifestyle factors, and showed significance for sleep and physical activity. We also showed that the epigenetic score for smoking was significantly correlated with most of the epigenetic clocks tested, except for two first-generation clocks. Conclusions Our study suggests that a more rapid return to never-smoker methylation levels after smoking cessation may be achievable in people who change their lifestyle in terms of physical activity and sleep duration. As cigarette smoking has been implicated in the literature as a leading cause of epigenetic aging and AHRR appears to be modifiable by multiple exogenous factors, it emerges as a promising target for intervention and investment.

Abstract Background Various studies have used different exercise protocols as post-activation performance enhancement (PAPE) stimulus; however, little attention has been given to the effects of exercise range of motion on the PAPE effect and subsequent performance enhancement. This study aimed to compare the PAPE responses induced by the bench press performed with different ranges of motion on subsequent bench press throw performance. Methods Ten resistance-trained males (age: 26 ± 3 years; body mass: 93.2 ± 9.4 kg; height: 181 ± 6 cm; experience in resistance training: 6.3 ± 2.4 years; relative bench press one-repetition maximum (1RM) 1.54 ± 0.2 kg/body mass) performed four experimental sessions consisting of a single set of the bench press at 80%1RM until mean barbell velocity dropped by 10% as the conditioning activity (CA) with a (1) standard, (2) cambered, (3) and reversed cambered barbell or a control condition in which the participants did not perform any CA. To assess the PAPE effect, single-sets of 2 repetitions of the bench press throw at 30%1RM were performed before and after the CA at the following time points: 2, 4, 6, 8, 10 min. Results The two-way ANOVA (4 conditions × 2time points) showed a significant interaction for peak power (p

Abstract Background Post-activation performance enhancement (PAPE) is a physiological phenomenon that acutely improves voluntary muscular performance following a conditioning activity. A large and growing body of literature has investigated different strategies to induce a PAPE stimulus; however, little attention has been given to whether acute caffeine ingestion could augment the effect of PAPE on subsequent performance. This study evaluated the acute effects of caffeine ingestion and back squat conditioning activity on subsequent countermovement jump (CMJ) performance in female semi-professional volleyball players. Methods Fourteen resistance-trained female volleyball players (26 ± 3 years) performed 3 different testing conditions in randomized order: where each ingested 6 mg/kg of caffeine (CAF) or placebo (PLAC) and performed a single set of back squats at 80%1RM until mean movement velocity dropped by 10% as the conditioning activity or a control (CTRL) condition where participants did not ingest any supplement and did not perform the conditioning activity. CMJ height was examined at baseline and in 2 min intervals until 10 min postconditioning activity. Furthermore, due to the wide inter-individual variation in optimal recovery time of PAPE response, the baseline and best post-conditioning activity performance were also analyzed. Results The Friedman test revealed a significant difference in jump height within CTRL (p = 0.002) and CAF (p = 0.001) conditions, but no significant difference was found within the PAP condition. The post hoc showed a significant decrease in jump height in 8th min in CTRL condition (p = 0.022, effect size [ES] = −0.31), a significant increase in jump height in 2nd min in CAF condition (p = 0.013, ES = 0.3), without differences in PLAC condition in comparison to baseline values. Moreover, a significant jump height increases from baseline to best performance post conditioning activity value for CAF (p = 0.001, ES = 0.39) and PLAC (p = 0.001, ES = 0.3) condition, but no significant difference was found for the CTRL condition. Conclusions The single set of heavy-loaded back squats with controlled velocity used as a conditioning activity in the current study enhanced subsequent CMJ performance in female volleyball players with no additional effect of caffeine.