Accuracy of Hidden Markov Models in Identifying Alterations in Movement Patterns during Biceps-Curl Weight-Lifting Exercise

This paper presents a comparison of mathematical and cinematic motion analysis regarding the accuracy of the detection of alterations in the patterns of positional sequence during biceps-curl lifting exercise. Two different methods, one with and one without metric data from the environment, were used to identify the changes. Ten volunteers performed a standing biceps-curl exercise with additional loads. A smartphone recorded their movements in the sagittal plane, providing information on joints and barbell sequential position changes during each lift attempt. An analysis of variance revealed significant differences in joint position (p < 0.05) among executions with three different loads. Hidden Markov models were trained with data from the bi-dimensional coordinates of the joint positional sequence to identify meaningful alteration with load increment. Tests of agreement tests between the results provided by the models with the environmental measurements, as well as those from image coordinates, were performed. The results demonstrated that it is possible to efficiently detect changes in the patterns of positional sequence with and without the necessity of measurement and/or environmental control, reaching an agreement of 86% between each other, and 100% and 86% for each respective method to the results of ANOVA. The method developed in this study illustrates the viability of smartphone camera use for identifying positional adjustments due to the inability to control limbs in an adequate range of motion with increasing load during a lifting task.info:eu-repo/semantics/publishedVersio

Custo energético durante a prática do Kendō e proposição de protocolo específico para avaliação da aptidão aeróbia em praticantes

Enquanto luta, o Kendō apresenta movimentos dinâmicos e estáticos, com manejo da espada em diferentes planos e amplitudes articulares, além do deslocamento vertical e horizontal do corpo. Este estudo teve por objetivo quantificar o custo energético (Ė) durante a prática do Kendō, bem como analisar a aptidão aeróbia de seus praticantes (consumo máximo de oxigênio (V̇O2max), limiar de permuta gasosa (LPG) e ponto de compensação respiratória (PCR)) e propor um protocolo progressivo máximo com técnicas do Kendō para a avaliação específica da aptidão aeróbia. Dez participantes homens (29,0 ± 7,6 anos, 82,0 ± 14,2 kg, 174,4 ± 7,5 cm) foram submetidos à (1) avaliação da composição corporal pelo DXA, (2) teste progressivo em esteira para avaliação cardiorrespiratória, (3) protocolo de desempenho: 11 exercícios de aquecimento e 31 de waza, aplicando técnicas de Kendō e (4) protocolo específico para o Kendō. Parâmetros ventilatórios foram amostrados respiração-a-respiração, usando uma unidade portátil (K4b2, COSMED®). O Ė (kcal×min-1) foi obtido pela equação: Ė = 3,941 × V̇O2 + 1,106 × V̇CO2. Para cada fase do protocolo (aquecimento e waza) foram considerados: ĖPico (ĖPicoAquec e ĖPicoWaza, em kcal×min-1), ĖMédia (ĖMédiaAquec e ĖMédiaWaza, em kcal×min-1) e ĖTotal (ĖTotalAquec, ĖTotalWaza e ĖTotalProt, em kcal). A transformação em equivalente metabólico (MET) foi realizada com o emprego da constante 4.184 (kJ×kg-1×h-1) a partir do V̇O2 de repouso (avaliado na posição sentada durante 10 minutos). A quantidade (gramas) e taxa (gramas∙min-1) de oxidação de carboidratos (CHO) e gorduras (FAT) foi determinada por: CHO = 4,585 V̇CO2 – 3,226 V̇O2 e FAT = 1,695 V̇O2 – 1,701 V̇CO2. O coeficiente de Pearson analisou as correlações entre as variáveis do custo energético e da composição regional e corporal. Em todas as análises adotou-se  ≤ 0,05. Os valores de ĖTotal foram: 76,2 ± 13,2 kcal (ĖTotalAquec) e 142,2 ± 26,5 kcal (ĖTotalWaza). Os valores de pico foram: 13,5 ± 2,7 kcal×min-1 (ĖPicoAquec) e 14,3 ± 2,9 kcal×min-1 (ĖPicoWaza). Em METs, os valores alcançaram picos de 6,9 ± 1,4 e 7,7 ± 1,8 kJ×kg-1×h-1 durante a execução do aquecimento e waza, respectivamente. As quantidades de CHO e FAT utilizadas foram 21,5  7,4 gramas e 2,0  1,1 gramas (aquecimento) e 52,0  6,4 gramas e 0,1  0,2 gramas (waza). A massa total e área regional e corporal não diferem quanto à influência sobre as variáveis de Ė e oxidação de substratos, porém a massa isenta de gordura regional (MIG) é mais influente sobre as variáveis de Ė, quando comparada à MIG corporal. Assim, a demanda energética durante a execução das técnicas do Kendō está associada à área e à quantidade de tecido regional metabolicamente ativo.As fighting, the Kendō is a combination of dynamic and static movements handling the sword in different plans and range of motion, as well as vertical and horizontal body displacement. This study aimed to quantify the energy cost during the practice of Kendō, and also analyze the aerobic level of the practitioners (maximal oxygen consumption (V̇ O2max), gas exchange threshold (GET) and respiratory compensation point (RCP)), and finally propose a progressive protocol from Kendō techniques to the specific assessment of aerobic condition. Ten male participants (29.0 ± 7.6 years, 82.0 ± 14.2 kg, 174.4 ± 7.5 cm) were underwent (1) assessing body composition by DXA, (2) progressive treadmill test for cardiac evaluation, (3) Performance protocol: 11 warm-up exercises and 31 waza, applying techniques Kendō, and (4) specific Kendō protocol. Ventilatory parameters were sampled breath-by-breath using a portable unit (K4b2 , Cosmed). The Ė (kcal×min-1 ) was obtained from: Ė = 3.941 × 1.106 × V̇ O2 + V̇ CO2. For each phase of the protocol (warm-up and waza) were considered: ĖPeak (ĖPeakWarm and ĖPeakWaza, in kcal×min-1 ), ĖMean (ĖMeanWarm and ĖMeanWaza, in kcal×min-1 ), and ĖTotal (ĖTotalWarm, ĖTotalWaza and ĖTotalProt, in kcal). The metabolic equivalent (MET) was obtained by the constant 4.184 (kJ× g-1 ×h-1 ) from the rest V̇ O2 (measured in sited position for 10 minutes). The amount (grams) and rate (grams×min-1 ) for carbohydrate (CHO) and fat (FAT) oxidation were measured from CHO = 4,585 V̇ CO2 – 3,226 V̇ O2 e FAT = 1,695 V̇ O2 – 1,701 V̇ CO2. The Pearson’s coefficient analyzed the correlation between the variables of energy cost and regional/whole body composition. The level of significance was set at  ≤ 0.05. The values for ĖTotal were: 76.2 ± 13.2 kcal (ĖTotalAquec) and 142.2 ± 26.5 kcal (ĖTotalWaza). The peak values were: 13.5 ± 2.7 kcal×min-1 (ĖPeakWarm) and 14.3 ± 2.9 kcal×min-1 (ĖPeakWaza). The MET values reached peaks at 6.9 ± 1.4 and 7.7 ± 1.8 kJ×kg-1 ×h-1 during the warm-up and waza, respectively. The amount of CHO and FAT oxidized were 21.5  7.4 grams and 2.0  1.1 grams (warm-up), and 52.0  6.4 grams and 0.1  0.2 grams (Waza). The regional and whole-body total mass and area had no different for the influence on the expenditure of Ė and substrate, although regional FFM exerted greater influence on Ė variables than whole-body FFM have presented. Thus, the energy demand during Kendō performance is related to the area and the amount of regional tissue metabolically active

Exercise domain profile through pulmonary gas exchange response during kendo practice by men

Background & Study Aim: The metabolic rate demanded during the practice of kendo techniques has not been reported, despite of it importance to physical training program. This study aimed to characterize exercise intensity during kendo practice based on pulmonary gas exchange profiles.Material & Methods: Nine skilled male athletes (29.7 +/- 7.8 years old, 174.9 +/- 9.1cm, 82.1 +/- 14.9kg body weight) underwent the following protocols: (1) body composition via DXA, (2) progressive treadmill test to assess (V) over dotO(2)max, gas exchange threshold (GET) and respiratory compensation point (RCP), and (3) 11 types of warm-ups using kendo techniques and 31 types of kendo waza. The techniques were performed twice, with a 24h break in between. The (V) over dotO(2) value was obtained using K4b2 (COSMED (R)) technology, and heart rate (HR) was recorded by 420sd (Polar (R)) frequencimeter.Results: The (V) over dotO(2) profile reached 84.7 +/- 13.5% (V) over dotO(2)max and 85.3 +/- 17.2% (V) over dotO(2)max at the end of warm-up and waza protocols, respectively. (V) over dotCO(2) showed the same profile: 83.5 +/- 9.40% and 81.1 +/- 13.7% (V) over dotCO(2)max for warm-up and waza. However, HR (97.8 +/- 3.3% and 103.4 +/- 3.6% HRmax) and (V) over dot(E) (90.1 +/- 15.6 and 107.8 +/- 13.2% (V) over dot(E)max) elicited values that were trunked to maximum rates at the end of warm-up and waza. The RER values at the end of warm-up (1.19 +/- 0.15) and waza (1.16 +/- 0.05) were greater than 1.1. All variables did not differ from their respective maximum rate values at the end of warm-up and waza (p <= 0.05, ANOVA with Tukey as post-hoc).Conclusions: Thus, (V) over dotO(2) and (V) over dotCO(2) profiles classified the kendo practice as a heavy domain exercise, while HR, E and RER classified it as a heavy-to-severe domain exercise.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Accuracy of Hidden Markov Models in Identifying Alterations in Movement Patterns during Biceps-Curl Weight-Lifting Exercise

This paper presents a comparison of mathematical and cinematic motion analysis regarding the accuracy of the detection of alterations in the patterns of positional sequence during biceps-curl lifting exercise. Two different methods, one with and one without metric data from the environment, were used to identify the changes. Ten volunteers performed a standing biceps-curl exercise with additional loads. A smartphone recorded their movements in the sagittal plane, providing information on joints and barbell sequential position changes during each lift attempt. An analysis of variance revealed significant differences in joint position (p &lt; 0.05) among executions with three different loads. Hidden Markov models were trained with data from the bi-dimensional coordinates of the joint positional sequence to identify meaningful alteration with load increment. Tests of agreement tests between the results provided by the models with the environmental measurements, as well as those from image coordinates, were performed. The results demonstrated that it is possible to efficiently detect changes in the patterns of positional sequence with and without the necessity of measurement and/or environmental control, reaching an agreement of 86% between each other, and 100% and 86% for each respective method to the results of ANOVA. The method developed in this study illustrates the viability of smartphone camera use for identifying positional adjustments due to the inability to control limbs in an adequate range of motion with increasing load during a lifting task

Academia da praça de esporte: suporte na promoção do bem-estar físico – Ações 2015

The activities of this social project aimed to analyze the relationship between the ideal body weight (PCIdeal) and the actual body weight (PCAtual) with maximum strength performance in one repetition to maximum test (1RM), as well as analyzing the validity of the modified and original Bryzcki’s equations to the estimation of force observed 1RM test among male students. Thus, 17 men were examined (24.1 ± 4.5 years, 176 ± 7.6 cm in height, and 77.8 ± 10.7 kg of body weight) and the maximum force through the test of 1RM in the bench-press exercises (SR) and leg-press 45º (LP45º). The 1RM test consisted of three series of determination and confirmation sets at 95, 100 and 105% 1RM applied randomly in 24 and 48 hours after 1RM. The PCAtual was determined by digital scales (TANITA) and PCIdeal was calculated by applying the bone diameters and height in the equation: Minimum Body Mass = (D/33.5)2 x 0.111 x M, where H (height, dm) and D (sum of 08 bone diameters: biacromial, chest, biiliac, bitrocantérico, knees, ankles, elbows, and wrists). The 1RM prediction equations were: LP45º: [1RM = (1.09703 × 5RM) + 14.2546], SR: [1 RM = (1, 1 307 × 5RM) + 0.6998)] and LP45º and SR: {1RM = (5RM ÷ [1.0278 - (0.0278 × N reps)]}. The validity was analyzed by the standard error of estimate (SEE) and the variance coefficient of determination (R2 ) Differences between PCAtual and. PCIdeal were analyzed by Student's T-test for independent data, as well as, the differences between 1RM in SR and LP45º. Correlations between PCAtual and PCIdeal with 1RM in SR and LP45º exercises were analyzed by Pearson’s coefficient (r). Both analyzes were performed using SPSS 18.0. The level of significance was set at  ≤ 0.05. The force values by 1RM test were 79.5 ± 15.9 kg for SR and 301.5 ± 66.4 kg for LP45º. The PCAtual (77.8 ± 10.7 kg) and the PCIdeal (59.7 ± 6.4 kg) differed each other ( < 0.01), correlating only to the LP45º 1RM (r = 0, 69,  = 0.002; and r = 0.72,  = 0.001, respectively). After the confirmatory tests, observed values of force in the 1RM test for SR and LP45º did not differ from the values of force for the estimative of 1RM from 5RM by modified equations (SR = 79.3 ± 15.7 kg and LP45º = 311.5 ± 66.3 kg,  = 0.97 and 0.81, respectively), and original (SR = 78.2 ± 15 6 kg, and LP45º = 304.8 ± 68.0 kg,  = 0.53 and 0.73, respectively). The absence of differences associated with low SEE and high explanatory coefficient (R2 ) in SR (SEE: 2.77 kg and R2 = 0.972) and LP45º (SEE: 9.82 kg and R2 = 0.979), confirm the validity of the two equations in predicting maximum strength between academics, as well as, the positive influence of body size and shape on the strength performance.As atividades do presente projeto de extensão tiveram por objetivo analisar a relação entre o peso corporal ideal (PCIdeal) e o peso corporal atual (PCAtual) com o desempenho máximo da força em teste de uma reptição máxima (1RM), assim como, analisar a validade das equações modificada e original de Bryzcki na predição da força em teste de 1RM entre universitários do sexo masculino. Foram analisados 17 homens (24,1± 4,5 anos, 176 ± 7,6 cm de estatura, e 77,8 ± 10,7 kg de peso corporal) quanto à força máxima pelo teste de 1RM, nos exercícios de supino horizontal (SR) e leg-press 45º (LP45º). O teste de 1RM foi composto por três séries de determinação, e séries de confirmação (à 95, 100 e 105%1RM) aplicadas randomicamente a 24 e 48 horas após o teste de 1RM. O PCAtual foi determinado por balança digital (TANITAÒ) e o PCIdeal foi calculado aplicando-se os diâmetros ósseos e estatura na equação: Massa Corporal Mínima = (D/33,5)2 x H x 0,111, onde H (estatura, dm) e D (soma de 08 diâmetros ósseos: biacromial, torácico, biilíaco, bitrocantérico, joelhos, tornozelos, cotovelos, e punhos). As equações de predição de 1RM foram: LP45º: [1RM = (1,09703 × 5RM) + 14,2546], SR: [1RM = (1,,1307 × 5RM) + 0,6998)] e LP45º e SR: {1RM = (5RM ÷ [1,0278 – (0,0278 × N reps)]}. A validade foi analisada pelo erro padrão da estimativa (EPE) e pelo coeficiente de explicação da variância (R2). As diferenças entre PCAtual e PCIdeal foram analisadas pelo Test-t de Student para dados independentes, assim como as diferenças entre 1RM em SR e LP45º. As correlações entre PCAtual e PCIdeal com 1RM nos exercícios de SR e LP45º foram analisadas pelo coeficiente de (r) Pearson. Ambas as análises foram processadas no SPSS 18.0. O nível de significância foi estabelecido em r ≤ 0,05. Os valores de força pelo teste de 1RM foram 79,5 ± 15,9 kg no SR e 301,5 ± 66,4 kg no LP45º. O PCAtual (77,8 ± 10,7 kg) e o PCIdeal (59,7 ± 6,4 kg) diferiram entre si (r &lt; 0,01), correlacionando-se apenas com 1RM no LP45º (r = 0,69, r = 0,002; e r = 0,72, r = 0,001, respectivamente). Após os testes confirmatórios, os valores de força observados no teste de 1RM no SR e LP45º, não diferiram dos valores de força para 1RM estimados a partir de 5RM pelas equações modificadas (SR = 79,3 ± 15,7 kg e LP45º = 311,5 ± 66,3 kg, r = 0,97 e 0,81, respectivamente), ou original (SR = 78,2 ± 15,6 kg e LP45º = 304,8 ± 68,0 kg, r = 0,53 e 0,73, respectivamente). A ausência de diferenças associada ao baixo EPE e elevado coeficente explanatório em SR (EPE: 2,77 kg e R2 = 0,972) e LP45º (EPE: 9,82 kg e R2 = 0,979), confirmam a validade de ambas as equações em predizer a força máxima entre universitários, bem como a influência positiva do tamanho e formato corporal sobre o desempenho de força

Tempo limite à velocidade aeróbica máxima em nadadores

info:eu-repo/semantics/publishedVersio

Physiological Responses During High-Intensity Interval Training in Young Swimmers

This study analyzed whether 100- and 200-m interval training (IT) in swimming differed regarding temporal, perceptual, and physiological responses. The IT was performed at maximal aerobic velocity (MAV) until exhaustion and time spent near to maximalVO2 peak oxygen uptake (⩒O2peak), total time limit (tLim), peak blood lactate [La−] peak, ⩒O2 kinetics (⩒O2K), and rate of perceived exertion (RPE) were compared between protocols. Twelve swimmers (seven males 16.1 ± 1.1 and five females 14.2 ± 1 years) completed a discontinuous incremental step test for the second ventilatory threshold (VT2), ⩒O2peak, and MAV assessment. The swimmers subsequently completed two IT protocols at MAV with 100- and 200-m bouts to determine the maximal ⩒O2 (peak-⩒O2) and time spent ≥VT2, 90, and 95% of ⩒O2peak for the entire protocols (IT100 and IT200) and during the first 800-m of each protocol (IT8x100 and IT4x200). A portable apparatus (K4b2) sampled gas exchange through a snorkel and an underwater led signal controlled the velocity. RPE was also recorded. The Peak-⩒O2 attained during IT8x100 and IT4x200 (57.3 ± 4.9 vs. 57.2 ± 4.6 ml·kg−1·min−1) were not different between protocols (p = 0.98) nor to ⩒O2peak (59.2 ± 4.2 ml·kg−1·min−1, p = 0.37). The time constant of ⩒O2K (24.9 ± 8.4 vs. 25.1 ± 6.3-s, p = 0.67) and [La−] peak (7.9 ± 3.4 and 8.7 ± 1.5 mmol·L−1, p = 0.15) also did not differ between IT100 and IT200. The time spent ≥VT2, 90, and 95%⩒O2peak were also not different between IT8x100 and IT4x200 (p = 0.93, 0.63, and 1.00, respectively). The RPE for IT8x100 was lower than that for IT4x200 (7.62 ± 2 vs. 9.5 ± 0.7, p = 0.01). Both protocols are considered suitable for aerobic power enhancement, since ⩒O2peak was attained with similar ⩒O2K and sustained with no differences in tLim. However, the fact that only the RPE differed between the IT protocols suggested that coaches should consider that nx100-m/15-s is perceived as less difficult to perform compared with nx200-m/30-s for the first 800-m when managing the best strategy to be implemented for aerobic power training.info:eu-repo/semantics/publishedVersio