Il costo energetico di varie forme di locomozione umana : implicazioni teoriche e pratiche

Lo scopo principale della tesi di dottorato è stato quello di studiare il costo energetico di varie forme di locomozione umana in diverse condizioni sperimentali. Nella fattispecie, le forme di locomozione e le condizioni sperimentali studiate, sono state: I. la corsa in linea ed a navetta, con metodica continua ed intermittente; II. la corsa a navetta intermittente con cambi di senso normali o rapidi, e gli effetti di 5 settimane di allenamento, sul costo energetico della corsa in linea ed a navetta intermittente; III. la corsa in linea ed a navetta intermittente in calciatori professionisti prima e dopo un periodo di allenamento; IV. lo yo-yo endurance test ed il costo energetico della corsa in linea in calciatori professionisti (serie C1) prima dopo sei mesi di allenamento e gare; V. la corsa in linea ed a navetta : differenza tra calciatori professionisti e maratoneti amatori di buon livello; VI. il cammino in piano ed in salita, di soggetti, maschi e femmine, fisicamente attivi e gli effetti dell’allenamento sul costo energetico del cammino in piano ed in salita; VII. la pagayata di kayakers e canoisti (canoa canadese) appartenenti alla nazionale juniores di canoa kayak . Risultati principali: 1. il costo energetico della corsa a navetta intermittente può essere interpolata in modo univoco da una funzione che tenga conto dell’energia cinetica, che nella corsa continua, ovviamente , è nulla, mentre nella corsa intermittente a navetta varia in funzione della distanza e velocità (R2 0,970); 2. dopo 5 settimane di allenamento di corsa a navetta intermittente è migliorato il costo energetico sia della corsa a navetta su 18,5m e su 8,5m (6,10% P< 0,002 e 14,15% P<0,05), che della corsa in linea sul nastro trasportatore (7,06% P< 0,003); 3. nei calciatori dopo un periodo di allenamento di 2 o 6 mesi il costo energetico della corsa in linea, a 13,5 km/h sul nastro, peggiora in maniera significativa in tutti in tutte le squadre valutate (serie A, primavera, C1)(6,23% P< 0,01e 13,81% P< 0,0001); 4. il V’O2max misurato nello yo-yo endurance non è correlato con la distanza percorsa e con quello stimato (R2 0,264 e R2 0,263), e la percentuale di miglioramento del V’O2max misurato non è correlata con quella della distanza percorsa (R2 0,010); 5. il costo energetico della corsa a navetta è maggiore nei maratoneti rispetto ai calciatori presumibilmente perché il gesto non è specifico della disciplina praticata e quindi più dispendioso (8,8% P< 0,01). 6. il costo energetico del cammino in piano ed in salita è maggiore nei maschi rispetto alle femmine (in piano 4, 5, 6 km/h 0% + 16, 9.6 e 7.4% in salita a 5 km/h a pendenza del 5, 10, 15% + 14.3, 16.2, 13.9%) . 7. in kayakers e canoisti (canoa canadese) di alto livello abbiamo correlato la prestazione migliore realizzata in gara con quella calcolata teoricamente. Quest’ultima è stata ottenuta dalla relazione individuale tra Ėr = f (t) ed Ėmax = f (t), dove Ėr è la potenza metabolica richiesta per coprire la distanza in questione ed Ėmax è la massima potenza metabolica. Il tempo t per cui Ėr = Ėmax è stato assunto come il tempo teorico migliore sulla distanza considerata. Tempi e velocità teoriche individuali sono stati essenzialmente uguali a quelle misurate nelle recenti competizioni (R2 0,917).The main purpose of this thesis was to study the energy cost of various forms of human locomotion, in several experimental conditions specifically forms of locomotion, and experimental conditions, were: I. continuous and intermittent linear and shuttle running; II. intermittent shuttle running with normal or fast changes of direction, and the effects of 5 weeks of training, on the energy cost of the linear or shuttle intermittent running; III. linear and shuttle intermittent running of professional soccer players before and after a training period; IV. yo-yo endurance test and the energy cost of running on line of professional soccer players (Category: Serie A, Primavera, C1) before and after six months of training competition; V. linear and shuttle running: the difference between professional soccer players and amateur marathoners of good level; VI. walking on flat terrain and uphill of male and female physically active subjects, and the effects of training on the energy cost of horizontal surface or uphill walking; VII. Paddling of the kayakers and canoeists (Canadian canoe) belonging to National Junior Canoeing Kayak. Main results: 1. the energy cost of intermittent shuttle running can be univocally interpolated uniquely by a function taking into account the kinetic energy that, in the continue run, of course, is zero, but in the intermittent shuttle run varies depending on distance and speed (R2 0,970); 2. after 5 weeks of intermittent shuttle running training, the corresponding energy cost over 18.5 m or 8.5 m increased by 6,10% P< 0,002 and 14,15% P<0,05, and that of linear running on the treadmill by 7,06% P< 0,003; 3. in soccer players, after a training period of 2 or 6 months, the energy cost of linear running at 13.5 km/h on the treadmill increased (i.e. became worse) significantly in all teams (Series A , spring, C1 ; by 6,23% (P< 0,01) and 13,81% ( P< 0,0001); 4. V'O2maxmeasured in the yo-yo endurance test is not correlated with the distance covered nor with estimated V'O2max value (R2 0,264 e R2 0,263); nor is the percentage improvement V’O2max correlated with the corresponding distance increase (R2 0,010); 5. the energy cost of shuttle running is higher in marathoners than in to soccer players probably because in the former case shuttle running is not specific to the practiced discipline and therefore more expensive (8,8% P< 0,01); 6. the energy cost of walking on the level or uphill treadmill is greater in males than in females (on flat terrain at 4, 5, 6 km/h by 16, 9.6and 7.4%; at 5 km/h on a 5, 10, 15 %incline by 14.3, 16.2 and 13.9 % respectively); 7. in high level kayakers and canoeists individual best performances achieved in practice were correlated with those theoretically calculated. In turn, these were obtained from the individual relationships Ėr=f(t) and Ėmax=f(t), where Ėr is the metabolic power required to cover the distance in question and Ėmax the maximal metabolic power. The time yielding Ėr=Ėmax was assumed to yield the best performance time. Individual theoretical best times and speeds were essentially equal to those measured during actual competitions(R2 0,917)

Infrared thermography-calorimetric quantitation of energy expenditure in biomechanically different types of jūdō throwing techniques: a pilot study

It was the purpose of this pilot study to assess the energy expenditure (EE) of two biome-chanically different jūdō throws, namely, the simple mechanical couple-based uchi-mata vs. the lever-based throw ippon-seoi-nage, using infrared thermal calorimetry (ITC). Testing subjects included one Caucasian female elite athlete (age: 26.4 years) and one male veteran jūdōka (age: 50.8 years). ITC images were captured by an Avio NEC InfRec R300 camera and thermal data obtained were plotted into a proprietary equation for estimation of EE. Data were compared to respiratory data obtained by a Cosmed K4 b2 portable gas analyzer. Oxy-gen consumption as estimated by ITC capture during practice of uchi-mata was markedly lower than during performance ippon-seoi-nage in the female (457 mL•min-1 vs. 540 mL•min-1, P<0.05) and male subject (1,078 mL•min-1 vs. 1,088 mL•min-1, NS), with the difference in values between both genders subject being significant (P<0.01). The metabolic cost of the exercise (uchi-mata vs. ippon-seoi-nage) itself was 1.26 kcal•min-1 (88 W) vs. 1.68 kcal•min-1 (117 W) (P<0.05) in the female subject, and 2.97 kcal•min-1 (207 W) (P<0.01) vs. 3.02 kcal•min-1 (211 W) (NS) in the male subject. Values for the female were significantly differ-ent (P<0.01) from those of the male subject. The results support the initial hypothesis that the couple-based jūdō throws (in this case, uchi-mata) are energetically more efficient than lever-based throws, such as ippon-seoi-nage. Application of this approach may be of practical use for coaches in optimizing energy-saving strategies in both elite and veteran jūdō athletes

Territorial survey on the interest in sport in the local territory of "Gian Camillo Glorioso" school

The latest survey by the Central Statistical Institute (ISTAT) in 2015 reports in Italy an increase in the number of sports practitioners compared to 2011. They are greater in girls and more distributed on the 4 age groups chosen as a representative sample. The chosen disciplines vary according to age classes and the previous survey, indicating a significant increase in dance for females and fitness for males. This study doesn’t focus on any reasons for the choices, on the related to the study or work activities and the data don’t emerge locally. The aim of the study is to investigate a limited area, an homogeneous sample based on high school students and to investigate possible motivations including the relationship with the study. Data show that more females (63%) than males (37%) replied to the questionnaire and that a third of the students study 3 hours a day. 60% of students practices sport and the most practiced ones are fitness (38%), dance (19%) and football (16%). The lack of time due to the study prevents physical activity for a third of the students, followed by a lack of motivation (30%) and facilities in the area (13%). In conclusion, results suggest that the study circumscribed locally, with a representative sample of the reference population is more reliable and can be used as a basis for any actions to be taken

Spatial genetic structure in the Eurasian otter (Lutra lutra) meta-population from its core range in Italy

We characterized the genetic structure of the Eurasian otter (Lutra lutra) meta-population living in the core of its Italian distribution range providing results from 191 fresh spraints, collected from 24 watercourses included in Southern Italy. Furthermore, according to ecological corridors and barriers, we discuss the likely ways of movement and possible evolutionary fate of these populations. We genotyped 136 samples using 11 Lut microsatellite nuclear markers amplified from faecal dna. Microsatellites were moderately variable (Ho = 0.45; He = 0.46), with a total number of alleles and average number of alleles per locus in the meta-population of 50 and 4.54, respectively. No significant heterozygosity excess was observed in meta-population suggesting no recent population bottlenecks. Bayesian clustering discriminated a sub-structuring of the meta-population in five putative clusters, indicating that local populations are genetically differentiated: three of these seem to be identifiable with geographically defined sub-populations (from the Cilento, Agri and Basento river basins). The fourth is represented by multiple sub-populations with admixed genotype, that include genotypes from the Lao, Sinni and Abatemaco river basins, living in a landscape with the higher environmental permeability. Landscape genetic analysis could provide evidence of an unexpected ecological corridor: the seacoast, highlighted, for the first time as a new way for the dispersion of the South-Italian otters. Deepening the knowledge of these perspectives is crucial to identify solid strategies aimed at the future health of the populations of the Italian otters, by restoring dispersal corridors and managing the watercourses

Energy cost differences between marathon runners and soccer players: Constant versus shuttle running

Purpose: In the last decades, the energy cost assessment provided new insight on shuttle or constant running as training modalities. No study, though, quantified the benefit of constant/shuttle running in soccer-players and runners. Therefore, the aim of this study was to clarify if marathon runners and soccer players present specific energy cost values related to their training experience performing constant and shuttle running.Methods: To this aim, eight runners (age 34 ± 7.30y; training experience 5.70 ± 0.84y) and eight soccer-players (age 18.38 ± 0.52y; training experience 5.75 ± 1.84y) were assessed randomly for 6’ on shuttle-running or constant-running with 3 days of recovery in-between. For each condition, the blood lactate (BL) and the energy cost of constant (Cr) and shuttle running (CSh) was determined. To assess differences for metabolic demand in terms of Cr, CSh and BL over the two running conditions on the two groups a MANOVA was used.Results:V·O2max were 67.9 ± 4.5 and 56.8 ± 4.3 ml·min−1 kg−1 (p = 0.0002) for marathon runners and soccer players, respectively. On constant running, the runners had a lower Cr compared to soccer players (3.86 ± 0.16 J kg−1m−1 vs. 4.19 ± 0.26 J kg−1 m−1; F = 9.759, respectively; p = 0.007). On shuttle running, runners had a higher CSh compared to soccer players (8.66 ± 0.60 J kg−1 m−1 vs. 7.86 ± 0.51 J kg−1 m−1; F = 8.282, respectively; with p = 0.012). BL on constant running was lower in runners compared to soccer players (1.06 ± 0.07 mmol L−1 vs. 1.56 ± 0.42 mmol L−1, respectively; with p = 0.005). Conversely, BL on shuttle running was higher in runners compared to soccer players 7.99 ± 1.49 mmol L−1 vs. 6.04 ± 1.69 mmol L−1, respectively; with p = 0.028).Conclusion: The energy cost optimization on constant or shuttle running is strictly related to the sport practiced

Modulation of synaptic plasticity by short-term aerobic exercise in adult mice

Physiological effects of different types, of continuous and interval aerobic training, have been largely described and studied in the adult man. It was previously indicated that interval training plays an important role in maximizing both peripheral muscle and central cardiorespiratory adaptations, permitting significant functional improvement even in healthy sedentary subjects. Since the outcome of different aerobic training trials on cognitive processes had never been evaluated, we compared, on an experimental mouse model, the effects of four training exercise protocols, named respectively C100, I100, C50 and I50 depending on the volume and on the type of training proposed, continuous or interval method. Therefore, to asses quantitative and qualitative functional changes, we analyzed several physical parameters before and after 6 weeks training in all four groups with respect to the control sedentary animals and we studied synaptic plasticity, by extracellular in vitro recordings, in hippocampal mouse slices, a region involved in learning and memory processes. We found that all four protocols of exercise applied in this study exerted positive effects on both physical and training parameters inducing weight augmentation, strength endurance and aerobic endurance increase, and potentiation of motor coordination. However, the improvement observed failed to induce an enhancement in synaptic plasticity in three out of four exercise protocols and only in the slices from mice trained with the interval 50% volume exercise the long term potentiation (LTP) increased with respect to the sedentary group. These findings suggest that motor activity exerts positive effects on cognitive processes provided that certain principles are respected, such as the training load and the elements of which it is composed, in order to plan the right quantitative and qualitative parameters and the appropriate recovery periods