Bioenergetics, Training and Performance in Distance Running

There has always been great interest from the scientific community on identifying training strategies to improve performance in long distance races. Most of the studies have focused on elite athletes, although amateur runners represent the majority of participants in endurance events. The need to study strategies for amateur athletes stems from their limited technical skills and the lack of time available for training compared to elite athletes. The purpose of the first study was to evaluate the effect of flywheel strength training and high intensity training protocols on RE and strength parameters in a group of recreational runners. Twenty-nine recreational runners were recruited to take part in the study and were randomly assigned to flywheel strength training (FST; n = 9; 44.5\ub16.0yrs; V\u2019O2max 48.8\ub15.2 ml min-1 kg-1), high intensity training (HIT; n = 9; 42.2\ub18.6yrs; V\u2019O2max 50.3\ub13.7ml min-1 kg-1) or low intensity training (LIT; n = 11; 45.4\ub18.0yrs; V\u2019O2max 50.2\ub16.8ml min-1 kg-1) groups. Before and after 8 weeks of an experimental period, maximal oxygen uptake (V\u2019O2max), ventilatory thresholds (VT), maximal dynamic force (1RM) and anthropometric data were evaluated. The FST group showed significant increases (p < 0.05) in 1RM and RE. No differences were found in the other groups. Anthropometric data were unchanged after the training period. The results of this study indicate that in recreational runners, flywheel strength training seems able to obtain improvements in RE and neuromuscular adaptation. In the second study, the aim was to compare the effects of different training distribution on changes in limiting factors and performance. The main difference between training model is the distribution of time spent in different HR zone, 77/3/20 % and 40/50/10 % of total training time for Polarized Endurance Training (PET) and Focused Endurance Training (FET). Training program included four training sessions per week for PET and 3 for FET. Thirty-eight recreational runners were recruited to take part in the study. They were randomly assigned to PET (n = 19; 43.2\ub18.4yrs; V\u2019O2max 52.9\ub18.1 ml min-1 kg-1) and FET (n=19; 39.4\ub18.5yrs; V\u2019O2max 53.4\ub18.3 ml min-1 kg-1) for an 8-week period. The training plans was designed to reach a similar score for both total TRIMP accumulated over 8 weeks (2492 \ub1 72.1 TRIMPs) and mean TRIMP accumulated each week (311 \ub1 9). Before and after training periods all the subjects performed laboratory incremental test to exhaustion to individualized V\u2019O2max, ventilatory threshold and intensity hr zone based on it, field performance test on 2km and 21km and muscle function tests 1RM, Squat jump (SJ) and Counter Movement Jump (CMJ). The total training time in 8 weeks was 29.8 \ub1 3.07 hours and 24.8 \ub1 1.96 for PET and FET group respectively, and no significant differences was found between groups in any investigated variable. Significant improvement from pre-to post training were observed in speed at V\u2019O2max (vV\u2019O2max), speed at VT2, speed at VT1 and RE for both groups. The results of this study are not able to define which approach is preferable with recreational runners in terms of intensity distribution. The strategies evaluated in this thesis show that the "recreational runners" model is able to provide data that meet research need and to respond to the training with adaptations similar to those recorded for elite athletes. Moreover, these strategies wants to represent for coaches and athlete alternative practices to the common training methods and ideas for future studies

Record of Jurassic mass transport processes through the orogenic cycle: Understanding chaotic rock units in the high-pressure Zermatt-Saas ophiolite (Western Alps)

The eclogite facies Zermatt-Saas ophiolite in the Western Alps includes a composite chaotic unit exposed in the Lake Miserin area, in the southern Aosta Valley region. The chaotic unit is characterized by a block-in-matrix texture consisting of ultramafic clasts and blocks embedded within a carbonate matrix. This unit overlies massive serpentinite and ophicarbonate rocks and is unconformably overlain by layered calcschist. Despite the effects of subduction and collision-related deformation and metamorphism, the internal stratigraphy and architecture of the chaotic unit are recognizable and are attributed to different types of mass transport processes in the Jurassic Ligurian-Piedmont Ocean. This finding represents an exceptional record of the preorogenic history of the Alpine ophiolites, marked by different pulses of extensional tectonics responsible for the rough seafloor topography characterized by structural highs exposed to submarine erosion. The Jurassic tectonostratigraphic setting envisioned is comparable to that observed in present-day magma-poor slow- and ultraslow-spreading ridges, characterized by mantle exposure along fault scarps that trigger mass transport deposits and turbiditic sedimentation. Our preorogenic reconstruction is significant in an eclogitized collisional orogenic belt in which chaotic rock units may be confused with the exclusive product of subduction-related tectonics, thus obscuring the record of an important preorogenic history. \ua9 2017 Geological Society of America

Cl-IB-MECA Inhibits Human Thyroid Cancer Cell Proliferation Independently of A3 Adenosine Receptor Activation

A3 adenosine receptor (A3AR) agonists have been reported to modulate cellular proliferation. This work was aimed to investigate the expression and the possible implication of A3AR in the human thyroid carcinomas. Normal thyroid tissue samples did not express A3 adenosine receptor, while primary thyroid cancer tissues expressed high level of A3AR, as determined by immunohistochemistry analysis. In human papillary thyroid carcinoma cell line, NPA, at concentrations > or =10 microM, the A3AR-selective agonist 2-chloro-N(6)-(3-iodobenzyl)adenosine-5'-N-methylcarboxamide (Cl-IB-MECA) produced inhibition of cell growth, by blocking the G(1) cell cycle phase in a concentration- and time-dependent manner. This effect was well correlated with a reduction of protein expression of cyclins D1 and E2 after 24 hours of Cl-IB-MECA treatment. Moreover Cl-IB-MECA induced dephosphorylation of ERK1/2 in a time- and concentration-dependent manner, which in turn inhibits cell proliferation. The effect of Cl-IB-MECA was not prevented by A3AR antagonists, MRS1191 or MRS1523 or FA385. Furthermore, neither nucleoside transporter inhibitors, Dypiridamole and NBTI, nor the A1, A2A and A2B receptors antagonists were able to block the response to Cl-IB-MECA. Although Cl-IB-MECA has been shown to influence cell death and survival in other systems through an A3AR-mediated mechanism, in NPA cells the growth inhibition induced by micromolar concentrations of Cl-IB-MECA is not related to A3AR activation and hence that its effects on human papillary carcinoma cell line seem to be independent of the presence of this receptor subtype

Effects of Different Training Intensity Distribution in Recreational Runners

Purpose: To compare the impact of two different training intensity distributions in terms of conditional and performance parameters and spent time to training in recreational athletes. Methods: Two different training intensity distribution model were performed for 8 weeks by 38 recreational runners. Runners recruited were randomly assigned to 2 different training models based on HR intensity detected with maximal test. The percentage distribution splitted in zone 1, 2 and 3 were by 77/3/20 and 40/50/10 in polarized endurance training group (PET) and focused endurance training (FOC) group respectively. Programs were balanced for total training impulse (TRIMP). To evaluate effects of training, before and after treatment were performed a maximal exercise test to determine Maximal Oxygen Uptake (V'O2max), Ventilatory Threshold (VT), respiratory-compensation point (RCT) Running Economy (RE) and 2 Km performance. To investigate the effects of training on muscular performance were performed one repetition maximum (1RM), squat jump (SJ) and counter movement jump (CMJ). Results: Both groups significantly improved their velocity at V'O2max (3.2% and 4.0%), at VT (4.0% and 3.2%), RCT (5.7% and 3.4%), the average velocity in 2 Km performance (3.5% and 3.0%) and RE (-5.3% and -8.7%) for PET and FOC respectively for each variable. No differences were found between the groups on any parameter investigated except about the total training time (PET = 29.8 3.1h and FOC = 24.8 2.0 h). Conclusion: Focused Endurance Training obtains similar improvements than Polarized Endurance Training saving 17% of training time in recreational runners

Статистический контроль качества испытаний фольги медной электролитической и катанки медной с использованием контрольных карт

Представлен метод статистического контроля правильности и повторяемости процесса проведения испытаний на основе трех фаз: сбора данных, анализа и управления процессом. Показан пример формирования подгрупп для контроля качества испытаний на примере катанки. Представлена причинно-следственная диаграмма Исикава для анализа процесса. Описан метод управления процессом.A method of the statistical surveillance of correctness and repeatability for tests carrying out process on basis of three phases is submitted: data collection, analysis and process control. The example of making up of subgroups for rod tests quality surveillance is shown. Isikava 's cause and effect diagram for process analysis is submitted. Process control method is described

Middle-distance running acutely influences the concentration and composition of serum bile acids. Potential implications for cancer risk?

BACKGROUND: This study was aimed to investigate the acute effect of medium-distance running on bile acids concentration and composition, in order to verify whether the positive impact of physical exercise on cancer risk may also be mediated by variation of bile acids concentration and composition in serum. METHODS: The concentration and composition of serum bile acids was analyzed in 30 middle-aged and healthy recreational athletes with a reference liquid chromatography-mass spectrometry technique, immediately before and shortly after the end of the running trial. The concentration of bile acids after the run was adjusted for plasma volume change. RESULTS: All athletes successfully completed the trial. After correction of values for the individual plasma volume change calculated after the run, the serum concentration of total bile acids was found to be significantly reduced by approximately 46%. A statistically significant decrease was observed for cholic, deoxycholic, chenodeoxycholic, ursodeoxycholic, glycoursodeoxycholic and hyodeoxycholic acids, whereas the concentration of the remaining compounds remained unvaried after the run. A considerable variation of bile acids profile was also observed. No significant association was found between running performance and variation of bile acids concentrations. CONCLUSION: These results show that middle distance running acutely decreases the concentration of total bile acids in serum, especially that of the more mutagenic and carcinogenic compounds, so providing an intriguing support to the favorable effects of physical exercise for lowering the risk of many gastrointestinal cancers

Sympatho-adrenergic activation by endurance exercise. Effect on metanephrines spillover and its role in predicting athlete\u2019s performance

Background: The sympatho-adrenergic activation during exercise is implicated in many cardiovascular respiratory and metabolic adaptations which have been thought to partially explain the different levels of performance observed between trained and untrained subjects. To date, no evidence exists about the association between competition performance and markers of \u201cacute stress response\u201d. We designed this study to investigate; (i) the acute sympatho-adrenergic activation during endurance exercise in recreational runners by measuring plasma levels of free metanephrine (MN) and normethanephrine (NMN) before and after a half-marathon run; (ii) the association between the metanephrines levels and the running time. Methods: 26 amateur runners (15 males, 11 females) aged 30 to 63 years were enrolled. The quantification of MN and NMN was performed by LC-MS/MS. Anthropometric ergonomic and routine laboratory data were recorded. Statistical analyses included paired T-test, univariate and multivariate regressions. Results: The post-run values of MN and NMN displayed a nearly 3.5 and 7 fold increase respectively compared to the baseline values (p < 0.0001 for both). NMN pre-run values and pre/post run delta values showed a significant direct and inverse association (p = 0.021 and p = 0.033, respectively) with running performance. No correlations were found for MN values. Conclusion: NMN is a reliable marker of sympatho-adrenergic activation by exercise and can predict endurance performance in the individual athlete. Adaptation phenomenon occurring not only in the adrenal medulla might represent the biological mechanism underlying this association. Further studies on sympatho-adrenergic activation, competition performance and training status should contemplate the measurement of these metabolites instead of their unstable precursors

Neuromuscular fatigue does not impair the rate of force development in ballistic contractions of submaximal amplitudes

The effect of muscle fatigue on rate of force development (RFD) is usually assessed during tasks that require participants to reach as quickly as possible maximal or nearmaximal force. However, endurance sports require athletes to quickly produce force of submaximal, rather than maximal, amplitudes. Thus, this study investigated the effect of muscle fatigue induced by long-distance running on the capacity to quickly produce submaximal levels of force. Twenty-one male amateur runners were evaluated before and shortly after a half-marathon race. Knee extensors force was recorded under maximal voluntary and electrically evoked contractions. Moreover, a series of ballistic contractions at different submaximal amplitudes (from 20 to 100% of maximal voluntary force) was obtained, by asking the participants to reach submaximal forces as fast as possible. The RFD was calculated for each contraction. After the race, maximal voluntary activation, resting doublet twitch, maximal force, and RFD during maximal contraction decreased (-12, -12, -21, and -19%, respectively, all P-values 0.4). Long-distance running impaired the capacity to quickly produce force in ballistic contractions of maximal, but not of submaximal, amplitudes. Overall, these findings suggest that central and peripheral fatigue do not affect the quickness to which muscle contracts across a wide range of submaximal forces. This is a relevant finding for running and other daily life activities that rely on the production of rapid submaximal contractions rather than maximal force levels

Neuromuscular Fatigue Does Not Impair the Rate of Force Development in Ballistic Contractions of Submaximal Amplitudes

The effect of muscle fatigue on rate of force development (RFD) is usually assessed during tasks that require participants to reach as quickly as possible maximal or near-maximal force. However, endurance sports require athletes to quickly produce force of submaximal, rather than maximal, amplitudes. Thus, this study investigated the effect of muscle fatigue induced by long-distance running on the capacity to quickly produce submaximal levels of force. Twenty-one male amateur runners were evaluated before and shortly after a half-marathon race. Knee extensors force was recorded under maximal voluntary and electrically evoked contractions. Moreover, a series of ballistic contractions at different submaximal amplitudes (from 20 to 100% of maximal voluntary force) was obtained, by asking the participants to reach submaximal forces as fast as possible. The RFD was calculated for each contraction. After the race, maximal voluntary activation, resting doublet twitch, maximal force, and RFD during maximal contraction decreased (-12, -12, -21, and -19%, respectively, all P-values &lt; 0.0001). Nevertheless, the RFD values measured during ballistic contractions up to 60% of maximal force were unaffected (all P-values &gt; 0.4). Long-distance running impaired the capacity to quickly produce force in ballistic contractions of maximal, but not of submaximal, amplitudes. Overall, these findings suggest that central and peripheral fatigue do not affect the quickness to which muscle contracts across a wide range of submaximal forces. This is a relevant finding for running and other daily life activities that rely on the production of rapid submaximal contractions rather than maximal force levels