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

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

Tempo limite à velocidade aeróbica máxima em nadadores

info:eu-repo/semantics/publishedVersio