101 research outputs found
Effects of High-Intensity Progressive Resistance Training Combined With Self-Talk on Muscle Strength and Functional Performance in Older Adults
No full textFerrando, V, Mirabelli, F, Panascì, M, Sofrà, D, Ruggeri, P, Faelli, E, and Bisio, A. Effects of high-intensity progressive resistance training combined with self-talk on muscle strength and functional performance in older adults. J Strength Cond Res XX(X): 000–000, 2025—In older people, muscle mass and functional capacity decline, affecting balance, and gait control. In this population, resistance training (RT) improves muscle strength, counteracting this physiological decline. In younger individuals, cognitive strategies like motivational self-talk have been successfully integrated with RT to enhance its effectiveness. This study aimed to compare the effects of a high-intensity progressive RT with positive motivational self-talk against RT alone on muscle strength and functional performance in older adults. Twenty-eight healthy older people were divided into resistance training self-talk (RT-ST) group and RT group. The RT-ST group mentally repeated positive motivational phrases during lower-limb exercises, whereas the other group performed RT alone. The 4-week protocol included biweekly sessions, consisting of warm-up, a high-intensity resistance exercise, and cooldown. Handgrip strength, 1 repetition maximum (1RM), 30-second chair stand (30 s-CS), and time up and go (TUG) tests were conducted before (PRE), immediately after (POST), and 2 weeks after follow-up (FU) of the intervention. One repetition maximum significantly increased from PRE to POST (p # 0.001) and FU (p # 0.05) in both groups. The 30 s-CS significantly improved only in the RT-ST group at FU (p # 0.001), with higher values compared with the RT group at POST (p # 0.05) and FU (p # 0.05). Time up and go test duration decreased in both groups (p # 0.001), with RT-ST completing the test faster than RT (p # 0.05). Incorporating positive motivational self-talk into a high-intensity progressive RT program led to significant improvements in functional performance, suggesting that its benefits go beyond improving muscle strength and may positively impact the activities of daily living in older adults
C-Peptide-based assessment of insulin secretion in the Zucker Fatty rat: a modelistic study.
No full textA C-peptide-based assessment of β-cell function was performed here in the Zucker fatty rat, a suitable animal model of human metabolic syndrome. To this aim, a 90-min intravenous glucose tolerance test (IVGTT) was performed in seven Zucker fatty rats (ZFR), 7-to-9 week-old, and seven age-matched Zucker lean rats (ZLR). The minimal model of C-peptide (CPMM), originally introduced for humans, was adapted to Zucker rats and then applied to interpret IVGTT data. For a comprehensive evaluation of glucose tolerance in ZFR, CPMM was applied in combination with the minimal model of glucose kinetics (GKMM). Our results showed that the present CPMM-based interpretation of data is able to: 1) provide a suitable fit of C-Peptide data; 2) achieve a satisfactory estimation of parameters of interest 3) quantify both insulin secretion by estimating the time course of pre-hepatic secretion rate, SR(t), and total insulin secretion, TIS, and pancreatic sensitivity by means of three specific indexes of β-cell responsiveness to glucose stimulus (first-phase, Ф(1), second-phase, Ф(2), and steady-state, Ф(ss), never assessed in Zucker rats before; 4) detect the significant enhancement of insulin secretion in the ZFR, in face of a severe insulin-resistant state, previously observed only using a purely experimental approach. Thus, the methodology presented here represents a reliable tool to assess β-cell function in the Zucker rat, and opens new possibilities for the quantification of further processes involved in glucose homeostasis such as the hepatic insulin degradation
Evaluation of Explicit Motor Timing Ability in Young Tennis Players
No full textA crucial ability for athletes playing sports that involve coincidence timing actions is the motor timing ability. The efficiency of perceptual and motor processes underlying the motor timing ability has been related to the motor experience gained in interceptive sports, such as tennis. In the present study, the motor timing ability in young tennis players (TP) and age-matched control participants (CTRL) was compared by means of a synchronization paradigm. Participants were asked to perform finger-opposition movements in synch to a metronome beating 0.5 and 2 Hz in (1) a bimanual coordination test, which compared the performance of the dominant hand with that of the contralateral hand, and (2) a movement lateralization test, which compared the motor performance of the dominant hand during single-hand and bimanual tasks (BTs). The motor performance was evaluated through movement strategy [defined by touch duration (TD), inter-tapping interval (ITI), and movement frequency] and movement accuracy (temporal accuracy defined by the synchronization error and spatial accuracy defined by the percentage of correct touches—%CORR_SEQ). Results showed that motor expertise significantly influences movement strategy in the bimanual coordination test; TD of TP was significantly higher than those of CTRL, specifically at 0.5 Hz. Furthermore, overall ITI values of TP were lower than those of CTRL. Lastly, in the movement lateralization test, the %CORR_SEQ executed with the right dominant hand by TP in the BT was significantly higher than those of CTRL. A discussion about the role of motor expertise in the timing ability and the related neurophysiological adaptations is provided
Power spectrum analysis of heart-rate variability in the young Zucker rat
No full textCardiac autonomic control was studied in a group of five young hyperinsulinaemic, insulin resistant, Zucker fatty rats (ZFR) compared with a control group of five young Zucker lean rats (ZLR). Power spectrum analysis (PSA) of heart rate variability (HRV) was performed with autoregressive (AR) models. All rats were anaesthetised with sodium pentobarbital. Mean insulinaemia and glycaemia levels were 185±27 μU/ml and 159±38 mg/dl, respectively, in the ZFR, and reduced to 13±13 μU/ml (p<0.05) and 101±15 mg/dl (p<0.05), respectively, in the ZLR. No significant difference in basal blood pressure was found between the two groups. Analysis of power spectrum density, normalized by the total area, showed a marked reduction (p<0.05) in the peak amplitude of the high frequency (HF) component in the ZFR group. No significant difference was observed in the peak amplitude of low frequency (LF) component between the two strains. LF/HF ratio was higher (p<0.05) in the ZFR group. These results indicate that in the young ZFR, hyperinulinemia associates with altered sympathovagal balance in the autonomic cardiovascular control, before the onset of significant changes in both sympathetic nervous activity and blood pressure
Estimation of first-phase insulin secretion in the Zucker Fatty Rat
No full textThe present study was designed to test the efficacy of the popular index AIRG(i.e. acute insulin response after glucose bolus) in the characterization of the first-phase insulin secretion in the Zucker Fatty Rat. The reliability of the AIRGwas evaluated by direct comparison with the first-phase β-cell responsiveness index (Φ1)provided by C-peptide minimal model. To this aim, AIRG and Φ1were simultaneously computed from IVGTT data, measured in six Zucker fatty rats (ZFR), 7-to-9week-old, and seven age-matched Zucker lean rats (ZLR). In the whole 13 rats population, the AIRG showed a significant linear correlation with Φ1(r = 0.89, P < 0.0001). Moreover, both Φ1(P < 0.05) and AIRG (p<0.001) showed a significant increase, in the ZFRs, compared to control group (ZLR). These findings suggest that the AIRG index is able to provide similar information of Φ1, in the evaluation of the alteration of the first-phase insulin secretion in Zucker Fatty Rats. Thus, the present study proposes the AIRG, as a suitable empiric index for a simple, reliable and low-cost quantification of the first-phase insulin secretion in Zucker Fatty Rats. © Springer International Publishing Switzerland 2016
Age-related analysis of insulin resistance, body weight and arterial pressure in the Zucker fatty rat
No full textThe evolution with ageing of insulin resistance, body weight (BW) and mean arterial pressure (MAP) was studied in a group of Zucker fatty rats (ZFRs, n =22), between 7 and 16 weeks of age, compared with an age-matched control group of Zucker lean rats (ZLRs, n =22). The minimal model of glucose kinetics was applied to estimate glucose effectiveness, SG, and insulin sensitivity, SI, frominsulinaemia and glycaemia measuredduring a 70 minintravenous glucose tolerance test. No correlation was found between SG and age in both ZFR and ZLR groups. No significant changes in mean SG between the two groups indicated no alteration of glucose-mediated glucose disposal. Estimates of SI from individual ZFRs were independent of age and, on average, showed 83% reduction (P <0.001) compared with the ZLR group. Despite the lack of alteration of SI with age, the ZFR group showed an age-related increase of MAP, which correlated with increasing BW(r =0.71 and P <0.001). These results support the hypothesis that in our ZFRs, as a suitable genetic model of obesity and hypertension, insulin resistance is fully established at the age of 7 weeks and remains practically unaltered until at least the sixteenth week. An age-related increase in arterial pressure, observed in this strain, relates more properly to increasing BW, rather than insulin resistance. Development of hypertension with increasing age and BW may result from an enhanced insulin-mediated activity of the sympathetic nervous system, as observed in our previously reported study
Minimal model based assessment of insulin resistance in relation to body weight in the Zucker fatty rat
No full textEnhanced beta-cell secretion in the zucker fatty rat assessed by minimal modeling of intravenous C-peptide data
No full textAction observation combined with conventional training improves the rugby lineout throwing performance: A pilot study
No full textCombining action observation (AO) and physical practice contributes to motor skill learning, and a number of studies pointed out the beneficial role of AO training in improving the motor performance and the athletes' movement kinematics. The aim of this study was to investigate if AO combined with immediate conventional training was able to improve motor performance and kinematic parameters of a complex motor skill such as the lineout throw, a gesture that represents a key aspect of rugby, that is unique to this sport. Twenty elite rugby players were divided into 2 groups. The AO group watched a 5-min video-clip of an expert model performing the lineout throw towards a target at 7 m distance and, immediately after the AO, this group executed the conventional training, consisting of 6 repetitions x 5 blocks of throws. The CONTROL group performed only the conventional lineout training. Intervention period lasted 4 weeks, 3 sessions/week. The AO group showed significant improvements in throwing accuracy (i.e. number of throws hitting the target), whilst no significant changes were observed in the CONTROL group. As concerns kinematic parameters, hooker's arm mean velocity significantly increased in both groups, but the increase was higher in AO group compared to CONTROL group. Ball velocity significantly increased only in the AO group, whereas ball angle release and ball spinning significantly decreased in both groups, with no differences between groups. Finally, no significant changes in knee and elbow angles were observed. Our results showed that the combination of AO and conventional training was more effective than a conventional training alone in improving the performance of elite rugby players, in executing a complex motor skill, such as the lineout. This combined training led to significant improvements in throwing accuracy and in hooker's and ball's kinematic parameters. Since AO can be easily implemented in combination with conventional training, the results of this study can encourage coaches in designing specific lineout training programs, which include AO cognitive training
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