Science & Technogym
Investigação científica e médica
A nossa equipa científica e médica garante que todos os produtos e soluções Technogym são informados pela investigação científica mais recente. Também promove o wellness lifestyle a nível global através de campanhas, conferências, seminários, publicações e colaborações com outros centros de pesquisa de prestígio.Saiba mais
Investigação e desenvolvimento
O nosso trabalho em investigação ajuda-nos a criar novos produtos e soluções para que as pessoas alcancem os seus objetivos de wellness. Cada novo produto requer uma média de 20 000 horas de trabalho de desenvolvimento e está sujeito a rigorosos controlos de qualidade e a extensos testes de resistência.Saiba mais
Enjoyment perception during exercise with aerobic machines.
Summary.-This study investigated enjoyment and naturalness of movement perceived during short bouts of exercise with three aerobic machines: treadmill, elliptical crosstrainer, and Vario. The participants were 72 experienced and 60 inexperienced users. Immediately after the exercise with each machine, they filled in a 12-item form of the Physical Activity Enjoyment Scale (PACES) and a Visual Analogue Scales (VAS) about naturalness of movement. Results showed significant within-subjects differences on all scales; exercise with the treadmill and Vario were perceived to be similarly enjoyable and more enjoyable and natural in comparison with the elliptical crosstrainer. Differences in naturalness ratings between experienced and inexperienced users were observed. Exercise was not equally enjoyable when performed with different aerobic machines, and this should be considered by professionals when prescribing aerobic training to enhance motivation and adherence.
Biomechanics of dumbbell/barbell and cable biceps curl exercises
Andrea Biscarini, Rita Borio, Francesco Coscia, Giovanni Mazzolai, Simonetta Simonetti, Gabriella Rosi
A two-dimensional model was developed for dumbbell/barbell and cable biceps curl exercises, in quasi-static and isokinetic regimes. Analytical expressions for the ratios of the biceps force (F) and the tangent (ft) and normal (fn) components of the joint reaction to the dumbbell (Mg) and cable (c) external load were deduced as a function of the joint angle q and the other relevant parameters. For standing/ preacher dumbbell curl, F and fn take their maximum values at the critical wrapping angle q*=27.4°, for any value of the preacher bench inclination a within the range 0²a²90°-q*. An increase of a yields: a) an increase in the initial value of F, and in the peak values of F and |fn| (up to 15Mg and 14Mg, respectively); b) a steeper decrease of F between q* and 180°-a where F=0; c) a shift of the ft(q) curve towards lower joint angles. For a³38°, the joint load becomes of compressive type (fn<0) within the whole range [0,180°-a] of the joint motion. In cable curl, high values of the distance dP of the elbow joint from the pulley center give the same results as the standing dumbbell curl (a=0). When dP approaches the smallest allowed values, the model predicts: a) a steep increase of F and a steep decrease of fn and ft, just above q=0; b) high peak values of F and |fn| at q=q* (up to 15c and 13c, respectively); c) tractional values of fn smaller than 2c and nearly constant values (~3c) of F, above q=100°.
The Italian Diabetes and Exercise Study (IDES): design and methods for a prospective Italian multicentre trial of intensive lifestyle intervention in people with type 2 diabetes and the metabolic syndrome.
BACKGROUND AND AIMS: The IDES is a prospective Italian multicentre randomized controlled trial to evaluate the efficacy of an intensive lifestyle intervention on modifiable cardiovascular disease (CVD) risk factors in a large cohort of people with type 2 diabetes and the metabolic syndrome.
METHODS AND RESULTS: We recruited 606 subjects with type 2 diabetes and waist circumference >94 cm (M) and >80 cm (F), plus >1 other metabolic syndrome trait (IDF criteria) for both sexes, aged 40-75 years, BMI 27-40 kg/m(2), diabetes duration >1 year with a sedentary lifestyle of >6 months. Patients were randomized into two groups: a control group, receiving conventional care including exercise counselling and an intervention group, treated with a mixed (aerobic and resistance) exercise programme (150 min/week) prescribed and supervised for 12 months. Primary outcome is HbA1c reduction. Secondary outcomes include other traditional and non-traditional risk factors and their relationship to exercise volume/intensity and fitness; dosage of glucose, lipid and blood pressure-lowering drugs; global CVD 10-year risk; patient well-being; and costs.
CONCLUSION: This trial verifies whether a prescribed and supervised exercise programme, including both aerobic and resistance training, is more effective than conventional exercise counselling in reducing modifiable CVD risk factors in type 2 diabetic subjects with the metabolic syndrome.
Joint Torques and Joint Reaction Forces During Squatting With a Forward or Backward Inclined Smith Machine
Andrea Biscarini, Fabio M. Botti, and Vito E. Pettorossi
We developed a biomechanical model to determine the joint torques and loadings during squatting with a backward/forward-inclined Smith machine. The Smith squat allows a large variety of body positioning (trunk tilt, foot placement, combinations of joint angles) and easy control of weight distribution between forefoot and heel. These distinctive aspects of the exercise can be managed concurrently with the equipment inclination selected to unload specific joint structures while activating specific muscle groups. A backward (forward) equipment inclination decreases (increases) knee torque, and compressive tibiofemoral and patellofemoral forces, while enhances (depresses) hip and lumbosacral torques. For small knee flexion angles, the strain-force on the posterior cruciate ligament increases (decreases) with a backward (forward) equipment inclination, whereas for large knee flexion angles, this behavior is reversed. In the 0 to 60 degree range of knee flexion angles, loads on both cruciate ligaments may be simultaneously suppressed by a 30 degree backward equipment inclination and selecting, for each value of the knee angle, specific pairs of ankle and hip angles. The anterior cruciate ligament is safely maintained unloaded by squatting with backward equipment inclination and uniform/forward foot weight distribution. The conditions for the development of anterior cruciate ligament strain forces are clearly explained.
Modeling of the knee joint load in rehabilitative knee extension exercises under water.
A biomechanical and hydrodynamic theoretical model has been developed in order to calculate the knee joint load during underwater knee extension exercises. The hydrodynamic force has been evaluated within the framework of a strip-theory approach, when a blunt rectangular resistive device is applied proximally to the shank to increase its frontal area. Analytical expressions of the patellar tendon force (F(PT)), the axial (phi(n)) and the shear (phi(t)) component of the tibiofemoral joint load have been derived as a function of joint angle (theta), angular velocity (theta ), angular acceleration (theta ), resistive device density, length (L(x)), width (L(z)) and thickness, and average hydrodynamic drag and added mass coefficients. An inverse dynamic problem has been solved, assuming for theta and theta a dependence on theta consistent with the experimental kinematic data available in the literature. The results highlight that the characteristics of the resistive device and the level of muscular activation can be adjusted reciprocally in order to control the peak value of F(PT), phi(n) and phi(t), and the position of these peaks within the joint range of motion (ROM). No anterior cruciate ligament (ACL) stress is observed (phi(t)>0) over the whole ROM, independent of the level of muscular activation, for a light resistive device with L(x) < or = 0.3 m and L(z) < or = 0.4 m. This work highlights that aquatic exercises can be usefully and safely implemented in the rehabilitation program following ACL surgery, and whenever it is important to avoid excessive shear joint forces that constrain the tibial plateau anterior translation with respect to the femur.
Minimization of the knee shear joint load in leg-extension equipment.
We developed an analytical biomechanical model for leg-extension equipment and the associated knee-extension/flexion exercises. The shear component, phi(t), of the tibiofemoral joint load was calculated taking into account all the fundamental elements of the equipment mechanics (resistance pad placement, cam/pulley system geometry, selected weight stack, etc.) and the instantaneous values of the relevant kinematical parameters (knee-flexion angle (theta(f)), angular velocity, and angular acceleration). The optimal distance (a(R))(OPT) between the knee-flexion/extension axis and the resistance pad placement point was derived by minimizing phi(t). (a(R))(OPT) is nearly independent of joint angular velocity and, for appreciably high resistance torques, becomes nearly independent of resistance level and cam/pulley geometry: for theta(f)>40 degrees , phi(t) is minimized by placing the resistance pad distally along the lower leg; for theta(f)<or=40 degrees, phi(t) can be completely eliminated by continuously moving the resistance pad proximally during knee-extension phase and distally during knee-flexion phase (0.17 m<or=(a(R))(OPT)<or=0.4 m). In the presence of knee angular accelerations and hamstrings co-contractions, not predictable in advance, the value of (a(R))(OPT) obtained neglecting these effects still represents a good compromise for joint protection. This work establishes the rational basis for the design and clinical use of a leg-extension equipment that minimizes phi(t).
Reliability and validity of the Mywellness Key physical activity monitor.
BACKGROUND: This study evaluated the reliability and criterion validity of the Mywellness Key accelerometer (MWK) using treadmill protocols and indirect calorimetry.
METHODS: Twenty-five participants completed two four-stage 20-minute treadmill protocols while wearing two MWK accelerometers. Reliability was assessed using raw counts. Validity was assessed by comparing the estimated VO(2) calculated from the MWK with values from respiratory gas exchange.
RESULTS: Good overall and point estimates of reliability were found for the MWK (all intraclass correlations > 0.93). Generalizability theory coefficients showed lower values for running speed (0.70) versus walking speed (all > 0.84), with the majority of the overall percentage of variability derived from the participant (68%-88% of the total 100%). Acceptable validity was found overall (Pearson's r = 0.895-0.902, P < 0.0001), with an overall mean absolute error of 16.22% and a coefficient of variance of 16.92%. Bland-Altman plots showed an overestimation of energy expenditure during the running speed, but total kilocalories were underestimated during the protocol by approximately 10%.
CONCLUSION: Good validity was found during light and moderate walking, while running was slightly overestimated. The MWK may be useful for clinicians and researchers interested in promotion or assessment of physical activity.
Anti-inflammatory effect of exercise training in subjects with type 2 diabetes and the metabolic syndrome is dependent on exercise modalities and independent of weight loss.
BACKGROUND AND AIMS: We investigated the effect of different exercise modalities on high sensitivity-C reactive protein (hs-CRP) and other inflammatory markers in patients with type 2 diabetes and the metabolic syndrome.
METHODS AND RESULTS: Eighty-two patients were randomized into 4 groups: sedentary control (A); receiving counseling to perform low-intensity physical activity (B); performing prescribed and supervised high-intensity aerobic (C) or aerobic+resistance (D) exercise (with the same caloric expenditure) for 12 months. Evaluation of leisure-time physical activity and assessment of physical fitness, cardiovascular risk factors and inflammatory biomarkers was performed at baseline and every 3 months. Volume of physical activity increased and HbA(1c) decreased in Groups B-D. VO(2max), HOMA-IR index, HDL-cholesterol, waist circumference and albuminuria improved in Groups C and D, whereas strength and flexibility improved only in Group D. Levels of hs-CRP decreased in all three exercising groups, but the reduction was significant only in Groups C and D, and particularly in Group D. Changes in VO(2max) and the exercise modalities were strong predictors of hs-CRP reduction, independent of body weight. Leptin, resistin and interleukin-6 decreased, whereas adiponectin increased in Groups C and D. Interleukin-1β, tumor necrosis factor-α and interferon-γ decreased, whereas anti-inflammatory interleukin-4 and 10 increased only in Group D.
CONCLUSION: Physical exercise in type 2 diabetic patients with the metabolic syndrome is associated with a significant reduction of hs-CRP and other inflammatory and insulin resistance biomarkers, independent of weight loss. Long-term high-intensity (preferably mixed) training, in addition to daytime physical activity, is required to obtain a significant anti-inflammatory effect.
Validation of the mywellness key in walking and running speeds.
This study was performed to assess the validity of the MyWellness Key (MWK) accelerometer during a treadmill-based protocol. The identification of different exercise intensities is imperative to objectively measure time spent at a specified exercise intensity. Thirty subjects, 15 men and 15 women (age = 24.5 ± 2.6 years; body mass index = 22.5 ± 2.5 kg·m(-1)), participated in a 4-phase treadmill protocol (5 minutes each one) using three different walking velocities (3, 4.5, and 6 km·h(-1)) and run (8 km·h(-1)) while outfitted with a MWK uniaxial accelerometer. Oxygen consumption was measured by indirect calorimetry (ICVO2).
RESULTS: The relationship between VO2 predicted from MWK (MWKVO2) and oxygen consumption (VO2 (ICVO2)), yielded a high and significant correlation (r = 0. 944; p < 0.001) with standard error of estimate (SEE) = 2.42 mL·kg(-1)·min(-1). The average differences between the two methods (MWKVO2 - ICVO2) were -0.79 (-8. 8% at 3 km·h(-1)), -0.02 (-0.2% at 4.5 km·h(-1)), 0.51 (3.3% at 6 km·h(-1)) and -0.74 (-2.7% at 8 km·h(-1)) ml·kg(-1)·min(-1). Only the 3 km·h(-1) speed showed a difference when compared to the criterion measure (p < 0.001). Bland and Altman analysis revealed less than a 1 MET difference in the mean at each point estimate and relatively tight distribution with the standard errors, especially with the 2 moderate walking speeds.
CONCLUSIONS: We found a high correlation between oxygen utilization and the MWK with low standard errors estimates. This indicates that this accelerometer can be used to identify exercise intensities that are related to walking and running. Key pointsFirst laboratory validation of a new uniaxial accelerometer, the MyWellness Key.Results indicate a good exercise intensity prediction during walking at moderate to high speeds.Comparing with other laboratory validations, MyWellness Key exercise intensity detection is aligned with other accelerometers.MyWellness Key can be used to give valid measurements for a range of ambulatory activity in addition to the capabilities to give real-time feedback to the participant in health promotion studies.
Determination and optimization of joint torques and joint reaction forces in therapeutic exercises with elastic resistance.
A model has been developed to definitively characterize the resistance properties and the joint loading (i.e., shear and compressive components of the joint reaction force) in single-joint exercises with ideal elastic bands. The model accounts for the relevant geometric and elastic properties of the band, the band pre-stretching, and the relative positioning among the joint center of rotation and the fixation points of the band. All the possible elastic torque profiles of ascending-descending, descending, or ascending type were disclosed in relation to the different ranges of joint angles. From these results the elastic resistance setting that best reproduces the average-user's knee extensor torque in maximal isometric/isokinetic efforts was determined. In this optimized setting, the shear tibiofemoral reaction force corresponding to an anterior (posterior) tibial displacement was 65% smaller than (nearly the same as) that obtained in a cam-equipped leg-extension equipment for equal values of resistance torque peak, whereas the compressive tibiofemoral reaction force was 22% higher. Compared to a weight-stack leg-extension equipment, an elastic resistance optimized setting has the potential to give a more effective quadriceps activation across the range of motion, and greatly reduces the anterior cruciate ligament strain force, which represents the main drawback of existing open kinetic-chain knee-extension exercises.
The effect of a strength training program on affect, mood, anxiety, and strength performance in older individuals
Silvano Zanuso, John C. Sieverdes, Nicholas Smith, Attilio Carraro, and Marco Bergamin
The purpose of this study was to evaluate the effect of a strength training program on anxiety, affect, and mood in a group of older adults (≥ 65 years). Twenty men and women participated in a 12-week strength training program. Participants were randomized to an intervention and a waiting list control group. Results showed a significant improvement in the intervention group’s strength scores. Trait anxiety showed a decline in both groups. When mood profiles of participants were analyzed across the initial 12-week of the study, a dimension of mood called Vigor-Activity significantly decreased in the control group while the intervention group’s scores did not change. The affect data showed that negative affect decreased significantly in the intervention group following the training protocol. This study indicates that 12 weeks of strength training results in significant muscle strength increases and moderate improvements of the overall psychological profile.
Evaluation of the MyWellness Key accelerometer.
OBJECTIVE: to examine the concurrent validity of the Technogym MyWellness Key accelerometer against objective and subjective physical activity (PA) measures.
DESIGN: randomised, cross-sectional design with two phases. The laboratory phase compared the MyWellness Key with the ActiGraph GT1M and the Yamax SW200 Digiwalker pedometer during graded treadmill walking, increasing speed each minute. The free-living phase compared the MyWellness Key with the ActiGraph, Digiwalker, Bouchard Activity cord (BAR) and Global Physical Activity Questionnaire (GPAQ) for seven continuous days. Data were analysed using Spearman rank-order correlation coefficients for all comparisons.
SETTING: laboratory and free-living phases.
PARTICIPANTS: sixteen participants randomly stratified from 41 eligible respondents by sex (n=8 men; n=8 women) and PA levels (n=4 low, n=8 middle and n=4 high active).
RESULTS: there was a strong association between the MyWellness Key and the ActiGraph accelerometer during controlled graded treadmill walking (r=0.91, p<0.01) and in free-living settings (r=0.73-0.76 for light to vigorous PA, respectively, p<0.01). No associations were observed between the MyWellness Key and the BAR and GPAQ (p>0.05).
CONCLUSIONS: the MyWellness Key has a high concurrent validity with the ActiGraph accelerometer to detect PA in both controlled laboratory and free-living settings.
Exercise for the management of type 2 diabetes: a review of the evidence.
Zanuso S1, Jimenez A, Pugliese G, Corigliano G, Balducci S.
The aim is to critically review the more relevant evidence on the interrelationships between exercise and metabolic outcomes. The research questions addressed in the recent specific literature with the most relevant randomized controlled trials, meta-analysis and cohort studies are presented in three domains: aerobic exercise, resistance exercise, combined aerobic and resistance exercise. From this review appear that the effects of aerobic exercise are well established, and interventions with more vigorous aerobic exercise programs resulted in greater reductions in HbA(1c), greater increase in VO(2max) and greater increase in insulin sensitivity. Considering the available evidence, it appears that resistance training could be an effective intervention to help glycemic control, especially considering that the effects of this form of intervention are comparable with what reported with aerobic exercise. Less studies have investigated whether combined resistance and aerobic training offers a synergistic and incremental effect on glycemic control; however, from the available evidences appear that combined exercise training seems to determine additional change in HbA(1c) that can be seen significant if compared with aerobic training alone and resistance training alone.
Biomechanics of Off-Center Monoarticular ExercisesWith Lever Selectorized Equipment
We have developed a 2-D analytical biomechanical model for monoarticular open kinetic-chain exercises with lever selectorized equipment, and different relative placement between the joint center of rotation (J) and the center of rotation (C) of the resistance input lever (“off-center” exercises). All the relevant geometrical aspects of such exercises have been characterized: the change with the joint angle of the distance between the resistance pad (P) and J, and of the angle between CP and JP (i.e., the angle between the resistance input lever and the exercising limb). These changes may strongly affect the joint load and the muscle torque in inverse dynamic problems, given the joint kinematics and the mass of the selected weight stack. Therefore, the muscle torque, the shear and axial components of the joint load have been calculated analytically as a function of the relative positioning of C and J, and the length CP, in addition to the parameters that define the joint kinematics, the equipment mechanics, and the external load. From these results we have derived the optimal cam profiles for “off-center” exercises, as well as the geometrical “off-center” setting that minimizes the shear component of the tibiofemoral joint load in leg extension equipment.
Episodic ataxia type 1 mutations affect fast inactivation of K+ channels by a reduction in either subunit surface expression or affinity for inactivation domain.
Episodic ataxia type 1 (EA1) is an autosomal dominant disorder characterized by continuous myokymia and episodic attacks of ataxia. Mutations in the gene KCNA1 that encodes the voltage-gated potassium channel Kv1.1 are responsible for EA1. In several brain areas, Kv1.1 coassembles with Kv1.4, which confers N-type inactivating properties to heteromeric channels. It is therefore likely that the rate of inactivation will be determined by the number of Kv1.4 inactivation particles, as set by the precise subunit stoichiometry. We propose that EA1 mutations affect the rate of N-type inactivation either by reduced subunit surface expression, giving rise to a reduced number of Kv1.1 subunits in heterotetramer Kv1.1-Kv1.4 channels, or by reduced affinity for the Kv1.4 inactivation domain. To test this hypothesis, quantified amounts of mRNA for Kv1.4 or Kv1.1 containing selected EA1 mutations either in the inner vestibule of Kv1.1 on S6 or in the transmembrane regions were injected into Xenopus laevis oocytes and the relative rates of inactivation and stoichiometry were determined. The S6 mutations, V404I and V408A, which had normal surface expression, reduced the rate of inactivation by a decreased affinity for the inactivation domain while the mutations I177N in S1 and E325D in S5, which had reduced subunit surface expression, increased the rate of N-type inactivation due to a stoichiometric increase in the number of Kv1.4 subunits.
Scientific Advisory Board
Diretor, Departamento Médico e Científico da TechnogymMais informações
Diretor médico, TechnogymMais informações
Professor de ciências do exercício no Departamento de Exercícios, Nutrição e Ciências da Saúde, Universidade de BristolMais informações
Diretor do programa de graduação em Promoção da Saúde e Wellness, Rocky Mountain University of Health ProfessionsMais informações
Presidente do Departamento de Ciências da Educação e Humanas no College of Education and Human Performace, Universidade da Flórida CentralMais informações
Professor Associado na Faculdade de Medicina da Universidade de PerugiaMais informações
Diretor do Laboratory of Preventive Medicine, Pennington Biomedical Research Centre, LouisianaMais informações
Professor na Arnold School of Public Health, Universidade da Carolina do SulMais informações