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Abstract The current study aimed to analyze the validity and reliability of the T-Force and Chronojump systems to measure the movement velocity in the leg press (LP) and chest press (CP) exercises in older people. Eighteen older adults (6 men and 12 women, 79.9 ± 8.5 years) performed a set of procedures over three weeks: (i) the first week was to familiarize participants with the testing procedures, (ii) the second was to perform a progressive loading test until reaching one-repetition maximum (1RM) in the LP and CP, and (iii) in the third week, participants performed three repetitions against five loads (40, 50, 60, 70, and 80% of 1RM). The mean velocity of each repetition was recorded simultaneously through the T-Force and Chronojump devices. Linear regressions (coefficient of determination [r2] and standard error of the estimate [SEE]) analyzed the inter-device validity, and Bland-Altman plots illustrated the systematic differences between devices. A mixed-effects model estimated the mean velocity differences between devices. The relative reliability was analyzed by the intra-class correlation coefficient (ICC[1,k]), while the absolute reliability was by the standard error of measurement (SEM) and the coefficient of variation (CV). The results showed that the T-Force and Chronojump presented a high association level in measuring mean velocity in the LP and CP (r 2 range: 0.96–0.99; SEE range: 0.01–0.02 m·s− 1) and low systematic bias (0.02–0.03 m·s− 1). The mean velocity values of T-Force were significantly higher than Chronojump only for 40% 1RM (p = 0.04). Excellent reliability inter-device (ICC range: 0.95–0.98; CV range: 1.7–3.2%) and intra-device (ICC range: 0.90–0.97; CV range: 3.4–6.5%) was observed. This study shows that the T-Force and Chronojump systems are valid and reliable for measuring movement velocity in the CP and LP machines when used by older adults.

ABSTRACT Background and Aims The current study aimed to compare the effects of 12 weeks of moderate versus high‐intensity water aerobics on muscle strength, body composition, lipid profile, blood pressure, and quality of life in both adults and older adults. Methods Twenty‐one women (65.19 ± 9.37 years) were randomly allocated to moderate (MIG; n = 11) or high‐intensity groups (HIG; n = 10). Both groups attended 45‐min sessions twice a week for 12 weeks. Assessments at baseline and posttraining included muscle endurance, explosive strength, body mass, body mass index, fat mass, fat‐free mass, triglycerides, total cholesterol, blood pressure, resting heart rate, general quality of life, and general health, and the physical, psychological, social relationships, and environmental domains of quality of life. Results HIG experienced greater reductions in cholesterol (ηp2 = 0.28) and fat mass (ηp2 = 0.35), and an increase in fat‐free mass (ηp2 = 0.35), compared to the MIG. The HIG also showed greater improvements in triglycerides (ηp2 = 0.24) and physical quality of life (ηp2 = 0.19) than MIG. No significant group × time interactions were found in the other variables. Nevertheless, muscular endurance and psychological quality of life were improved in both groups (p

Studies have revealed the efficacy of non-pharmacological therapeutic interventions in slowing or delaying the onset and evolution of symptoms. Among them is physical and cognitive stimulation (Ferretti, 2016; Hernandez, Coelho, Gobbi, & Stella, 2010), which, in turn, prevent motor inactivity through the practice of physical and cognitive exercises through the activation of specific neurological functions. So, the non-invasive brain activity modulation associated with the practice of physical exercises may improve elderlies' functional autonomy and cognition. The aim of this study was to assess the effect of non-invasive brain activity modulation technique, associated with the practice of physical exercises with high cognitive demand on the functional autonomy and cognitive variables of the elderly with mild cognitive impairments. The study was registered with the Brazilian Registry of Clinical Trials (UTN Number: U1111-1249-0494). One hundred and forty elderly diagnosed with MCI, aged 60 or over, of both sexes, were divided into two groups. A control group (CG, n = 68, = 74.6, and an experimental group (EG, n=70, = 71.4 ) were formed. The cognitive and functional variables of participants were measured. Non-invasive brain stimulation (NIBS) and physical exercises with high cognitive demand were used for intervention. The CG participants remained with their normal activities, which included participation in the memory workshop activities. The EG had sessions once a week, with a mix of NIBS protocol and practice exercises with high cognitive demand. Both groups got a 7-week period between the evaluations. Although we did not find significant differences in all assessed variables (figure 1), the EG group had better functional development. In our study, there was no strict control as to the intensity of motor tasks and no addition of overload in order to actually stimulate physiological mechanisms responsible for promoting gains in physical variables. The intervention promoted a reduction of dementia effects, despite the lack of statistical significance, the EG obtained more positive results when compared to the CG.

Alzheimer's disease (AD) is the most common neurodegenerative disease (Raskin et al., 2015). Noninvasive brain stimulation (NIBS) is another form of cognitive therapy that has received attention recently (Xu et al., 2019; Calomeni et al., 2017). To investigate whether a combination of Physical Exercise (PMED) and non-invasive brain stimulation (NIBS) can minimize some of the neurobiological impairments caused by Alzheimer's disease (AD). Eighty-eight older adults were divided into four groups (n=22), named GAE (AD receiving PMED plus NIBS), GCP (AD receiving PMED), GCN (AD receiving NIBS), and GCS (control. No intervention). Binaural beats are used in NIBS and PMED. BDNF and Tau proteins were determined from blood samples. Check alpha band and SMR rhythms by EEG. All surveys were blinded. Nonparametric tests with 5% significance and size effect tests were performed before and after the intervention. For GCS (p>0.05), no differences were found for all variables, and GCN and GCS showed no improvement in inhibitory control (p>0.05) or working memory (p>0.05). GCP and GAE increased executive function (p

With advancing age, some declines in health and physical fitness become expected. Considering that water aerobics is one of the aquatic activities most practised by adults and older adults, verifying its impact on the different parameters of physical fitness in these age groups is important. The main purpose of this study was to analyse the effect of 12 weeks of water aerobics on muscle strength and body composition in adults and older adults. Twenty individuals (63.95 ± 11.21 years old) performed 12 weeks of water aerobics twice a week (45 min/session). The water aerobics classes consisted of 5 minutes of warm-up (92.25 ± 8.67 bpm), 35 minutes of the main part of the class (119.22 ± 6.80 bpm), and 5 minutes of cool down (97.70 ± 7.62 bpm). The muscle strength (i.e., countermovement jump [CMJ], medicine ball throw [MBT], chair stand test [CST], forearm flexion [FF]) and body composition (i.e., fat mass [FM] and muscle mass [MM]) were evaluated before the training program and one week after the 12 weeks. After training, significant differences were observed in CST, FF, and CMJ (Table 1). Furthermore, although the differences were not significant, most of the other variables analysed showed slight improvements. Water aerobics appears to be an interesting aquatic modality when it is intended to improve the endurance strength of the upper and lower limbs and the explosive strength of the lower limbs in adults and older adults. When we desire to enhance anthropometric parameters, it seems necessary to consider the duration of the program, requiring at least 12 weeks of water aerobics.

We compared the effects of velocity-monitored resistance training with an intra-set velocity loss (i.e., the decrement in repetition velocity over the set) of 10 % vs. 20 % on strength-related outcomes in older adults. We randomly assigned eighteen older adults to a velocity loss group of 10 % (n = 10; 78 ± 12 years) or 20 % (n = 8; 73 ± 10 years) to perform a 10-week training program. The primary outcomes were the one-repetition maximum (1RM) and the average mean velocity against absolute loads associated with loads 0.05). Both groups improved the 1RM leg press from pre- to mid- and post-test and the MVlow and MVhigh from pre- to mid-test (p 0.05), but both increased the MVlow from pre- to mid-test (p

In cycling, drag is the force that opposes the cyclist's motion and is caused by the cyclist's and their equipment's interaction with the air. The surface area of the cyclist and their equipment, such as the bike, helmet and body postures, have a substantial impact on how much drag they encounter. This study compared the energy cost an able-bodied and shoulder amputee cyclist through numerical simulations using computer fluid dynamics. According to the hypothesis, an able-bodied cyclist may use more energy at a given speed than an able-bodied cyclist. For this study, a professional male cyclist who weighs 65 kg and is 1.72 m tall took part. The estimated energy cost was lower in an shoulder amputee in comparison to the able-bodied cyclist. Significant statistical differences and relationships were found between the cyclists for the 11 selected speeds. Altogether, this study allows to conclude that, for the same conditions, an able-bodied cyclist deliver less energy cost in comparison to a shoulder amputee.

It has been shown that training with resistance sled sprints (RSS) can improve running performance, but the effect of different RSS loads on sprint performance is unclear. This study aimed to examine this effect on running velocity, step frequency, and step length. Twenty-one collegiate track and field male athletes (20.6 ± 1.3 years) performed eight 60-m sprints with and without a resisted sled. The sled loads were individually set based on the participant's body mass (BM) and were applied in 10% increments from 20%–80% of BM. A 20-minute rest was allowed between trials. The running distance was divided into six 10-m phases. We analyzed the mean running velocity, step frequency, and step length at each phase, observing significant interactions in each. All indices decreased with increasing loads. Significant differences were observed in running speed and step frequency between all loads, except between 70%–80% of BM, and in the step length between all loads. Additionally, the maximum values for running velocity, step frequency, and length appeared in different phases according to the load. In addition to kinematics, coaches and athletes should focus on setting running distances and loads in RSS training.

AimThis study aimed to i) determine the load-velocity relationship in the seated chest press in older adults, ii) compare the magnitude of the relationship between peak and mean velocity with the relative load, and iii) analyze the differences between sexes in movement velocity for each relative load in the chest press.Material and methodsThirty-two older adults (17 women and 15 men; 79.6±7.7 years) performed a chest press progressive loading test up to the one-repetition maximum (1RM). The fastest peak and mean velocity reached with each weight were analyzed. Quadratic equations were developed for both sexes and the effectiveness of the regression model was analyzed through a residual analysis. The equations were cross-validated, considering the holdout method. The independent samples t-test analyzed i) the differences in the magnitude of the relationship between peak and mean velocity with the relative load and ii) the differences between sexes in the peak and mean velocity for each relative load.ResultsIt was possible to observe very strong quadratic load-velocity relationships in the seated chest press in women (peak velocity: r2 = 0.97, standard error of the estimate (SEE) = 4.5% 1RM; mean velocity: r2 = 0.96, SEE = 5.3% 1RM) and men (peak velocity: r2 = 0.98, SEE = 3.8% 1RM; mean velocity: r2 = 0.98, SEE = 3.8% 1RM) without differences (p>0.05) in the magnitude of the relationship between peak and mean velocity with the relative load. Furthermore, there was no overfitting in the regression models due to the high and positive correlation coefficients (r = 0.98-0.99). Finally, men presented higher (p0.05).ConclusionMeasuring repetition velocity during the seated chest press is an objective approach to estimating the relative load in older adults. Furthermore, given the velocity differences between older women and men at submaximal loads, it is recommended to use sex-specific equations to estimate and prescribe the relative loads in older adults.

Biomechanical analysis in swimming has been widely undertaken with propulsion and add-resistance materials. This approach tried to understand how coordination and stroke mechanics were influenced by using such aids. To date, just one study aimed to understand the effect of parachute on the propulsive force at different water flows in a flume (Schnitzler, Brazier, Button, Seifert, & Chollet, 2011). Thus, the aim of the current study was to analyse the effect of using a parachute on the kinetic and kinematic variables at different swimming velocities. An international female swimmer (age: 18 years-old) was recruited to perform three all-out trials in front-crawl at different swimming velocities (0.80, 1 and 1.20 m·s-1). This was done in two different conditions: free-swimming (FS) and swimming with a parachute (SP). The swimming velocity were controlled by a visual light pacer (DigiSwim Pacing System, Digiwest, PT) and the propulsive force (PF, N), was measured with a differential pressure system (Aquanex 4.1, STR, USA) allowing retrieve PF values for the dominant (PFD) and non-dominant (PFND) upper-limbs. The Symmetry Index (SyI, %) was calculated as reported elsewhere (Robinson, Herzog, & Nigg, 1987). The stroke frequency (SF, HZ) was assessed with a chrono-frequency meter (FINIS 3x300, Finis Inc., USA) and, therefore, the stroke length (SL, m·c-1) and stroke index (SI, m2·c-1·s-1) were estimated. Swimming with the parachute required higher propulsive forces in both limbs, as the velocity increased. The SyI showed a tendency to decrease, as the velocity and propulsive force increased. It seems that when the velocity is near to the maximum (50-m best personal record), a decrease in the deficit of the force applied by both limbs is shown, representing a more comfortable swim pace to use. Only the velocity of 1.20 m·s-1 showed a SyI bellow of 10% (cut-off value), being considered as a symmetric stroke. The SL and SI were lower in the parachute condition since the additional resistance led to a greater effort and SF. The SF presented an incremental increase within the different velocities. Swimming coaches should be aware of the hypothetical significant differences in kinetic and kinematic variables when using a parachute. The lower velocities should be avoided to maintain the integrity of the force applied and to reach a more symmetric motor pattern.

As variáveis antropométricas e a força muscular têm sido apontados como fatores determinantes para o rendimento em nadadores jovens (Morais et al., 2013). No entanto, a influência de algumas destas variáveis ainda não é clara na literatura. Com o presente estudo procuramos verificar de que forma as características antropométricas (i.e. altura, massa corporal e envergadura) e a força muscular explosiva poderão influenciar o rendimento desportivo no escalão juvenil, verificando a sua relação com as provas dos 50m e 400m livres. Foram avaliados 184 nadadores (idade: 14.64±0.80 anos; altura: 1.69±0.08m; massa corporal: 58.71±7.87kg),92 do sexo feminino e 92 do sexo masculino. Registaram-se as medidas antropométricas (massa corporal, altura e envergadura) de cada nadador. Seguiu-se a avaliação da força muscular explosiva dos membros inferiores e membros superiores, através do salto horizontal a pés juntos e do lançamento da bola medicinal (3kg), respetivamente. Em dias diferentes, foram realizadas as avaliações do rendimento (tempo) e de variáveis biomecânicas (distância de ciclo, frequência gestual, índice de nado) na prova dos 50m livres e dos 400m livres. Verificou-se uma correlação linear negativa entre a altura (r = -0.64 e r = -0.60, p

Paralympic Powerlifting is a sport in which the strength of the upper limbs is assessed through bench press performance in an adapted specific bench. It is therefore essential to optimize training methods to maximize this performance. The aim of the present study was to compare force production and muscle activation involved in partial vs. full range of motion (ROM) training in Paralympic Powerlifting. Twelve male athletes of elite national level in Paralympic Powerlifting participated in the study (28.60 ± 7.60 years of age, 71.80 ± 17.90 kg of body mass). The athletes performed five sets of 5RM (repetition maximum), either with 90% of 1RM in full ROM or with a load of 130% 1RM in partial ROM. All subjects underwent both exercise conditions in consecutive weeks. Order assignment in the first week was random and counterbalanced. Fatigue index (FI), Maximum Isometric Force (MIF), Time to MIF (Time) and rate of force development (RFD) were determined by a force sensor. Muscle thickness was obtained using ultrasound images. All measures were taken pre- and post-training. Additionally, electromyographic signal (EMG) was evaluated in the last set of each exercise condition. Post-exercise fatigue was higher with full ROM as well as loss of MIF. Full ROM also induced greater. EMG showed greater activation of the Clavicular portion and Sternal portion of pectoralis major muscle and lower in the anterior portion of deltoid muscle when full ROM was performed. Muscle thickness of the pectoralis major muscle increased post-exercise. We concluded that training with partial ROM enables higher workloads with lower loss of muscle function.

De entre as técnicas não invasivas de determinação do limiar anaeróbio, o método da determinação da velocidade crítica tem merecido grande atenção, nomeadamente no âmbito da avaliação e controlo do treino em natação. Neste sentido, o objetivo do presente artigo foi efetuar uma revisão da literatura do tipo qualitativa acerca do significado do parâmetro velocidade crítica e sua aplicação à natação. Foram abordadas questões relativas à origem e definição do conceito de velocidade crítica, às metodologias de determinação mais comuns, bem como uma breve referência ao conceito de velocidade crítica anaeróbia. A velocidade crítica é sugerida como um parâmetro não invasivo de avaliação do desempenho aeróbio e de predição do limiar anaeróbio de nadadores, independentemente do nível desportivo. As principais vantagens deste indicador resultam da facilidade de aplicação e análise num elevado número de nadadores, sem a necessidade da utilização de equipamentos dispendiosos ou de recolha de sangue. Aponta-se como uma ferramenta útil no mecanismo de prescrição e controlo de cargas de treino por meio de resultados em condições experimentais ou recorrendo a tempos obtidos durante as competições. A descriminação dos valores de velocidade crítica entre nadadores com diferentes perfis metabólicos (velocistas versus fundistas) e ainda a sua aplicabilidade em regime anaeróbio são aspetos que ainda carecem de um maior entendimento.

O objetivo deste estudo foi comparar as respostas da frequência cardíaca (FC), perceção subjetiva do esforço (PSE) e da concentração de lactato (LA) nas aulas de jump fit e hidro jump. A amostra foi constituída por 8 mulheres (43.5 ± 5.2 anos, 160.0 ± 4.68 cm, 58.93 ± 4.15 kg e 25.69 ± 4.40 %MG), todas elas praticantes das aulas de fit jump. O estudo envolveu três momentos de avaliação. Na primeira foram avaliadas as medidas antropométricas, FC e LA em repouso, bem como a familiarização e treino da aula do hidro jump e da Escala de BORG. No segundo e terceiro momento de avaliação foram recolhidas as variáveis durante o hidro jump e jump fit, com 48 horas de intervalo entre as avaliações. Foi realizada a estatística descritiva e a inferencial através da ANOVA one-way com o Post Hoc de Tukey para medir a FC e LA e o teste de Friedman seguido do teste de Wilcoxon para a PSE. O estudo admitiu o nível de significância de p < .05. Não houve diferenças estatisticamente significativas entre os valores médios de todas as variáveis estudadas. O jump fit produziu efeitos semelhantes nas variáveis estudadas no meio terrestre e aquático.