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1.
Aging Clin Exp Res ; 31(6): 837-844, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31115875

RESUMEN

BACKGROUND: Adequate nutrition and, especially, optimal protein intake are necessary to preserve physical function during aging. Increased consumption of animal-derived protein is often advocated as a strategy to support physical performance in old age. However, there is a lack of empirical evidence to support this claim. AIMS: To assess the relationship of protein consumption and specific protein sources with physical function in older adults. METHODS: Participants were community dwellers aged 60 years and older recruited in São Paulo, Brazil. Enrollees had their medical books reviewed and were evaluated for anthropometry, physical performance, and diet. Physical performance was evaluated by isometric handgrip strength and walking speed (WS) tests. Diet was assessed using a 24-h recall diary. RESULTS: Ninety older adults were recruited (mean age: 68.0 ± 6.7 years; 87.0% women). Body weight-adjusted protein consumption was significantly associated with upper-limb muscle strength (r = 0.21; p < 0.05), but not with usual (r = 0.09; p > 0.05) or fast WS (r = 0.08; p > 0.05). Conversely, relative protein consumption was correlated with usual WS (r = 0.13; p < 0.05), while fast WS was negatively associated with relative animal protein intake (r = - 0.18; p < 0.05) and positively associated with relative plant-based protein ingestion (r = 0.15; p < 0.05). DISCUSSION: Findings of the present study indicate that different measures of protein intake are associated with distinct components of physical function. In addition, high relative ingestion of vegetable protein is associated with faster WS. CONCLUSIONS: A comprehensive dietary evaluation is necessary to appreciate the impact of specific nutrients on physical performance in older people. Future interventional studies are needed to establish the optimal blend of protein sources to support physical performance in old age.


Asunto(s)
Estado Nutricional , Proteínas de Vegetales Comestibles/farmacología , Velocidad al Caminar/efectos de los fármacos , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Brasil , Estudios Transversales , Femenino , Humanos , Vida Independiente , Masculino , Persona de Mediana Edad , Evaluación Nutricional , Velocidad al Caminar/fisiología
2.
J Sports Sci Med ; 13(1): 59-65, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24570606

RESUMEN

The purpose of this study was to compare the influence of measuring the overall session rating of perceived exertion (session-RPE) at 10 vs. 30 minutes following exercise. Eight boxers completed three different standardized training sessions of different intensities (easy, moderate and hard) in a matchedpairs, randomized research design. Exercise intensity was assessed during each bout by measuring heart rate, blood lactate concentration and session-RPE. To assess the effect of measurement timing on session-RPE, RPE data were collected either 10 or 30 minutes post-exercise. There was no significant effect of measurement time on session-RPE values following easy (10 minutes: session-RPE = 1.3 ± 1.0 Arbitrary Unit (AU), %Heart Rate Reserve (HRR) = 49.5 ± 11.1, and ∆Blood lactate = -2.3 ± 16.3%; 30 minutes: session-RPE = 1.7 ± 1.0 AU, %HRR = 51.3 ± 10.8, and ∆Blood lactate = 0.7 ± 25.2%), moderate (10 minutes: session-RPE = 2.7 ± 1.6 AU, %HRR = 67.2 ± 10.8, and ∆Blood lactate = 2.2 ± 19%; 30 minutes: session-RPE = 2.5 ± 0.9 AU, %HRR = 67.2 ± 5.9, and ∆Blood lactate = 24.5 ± 17.1%) and hard (10 minutes: session-RPE = 5.7 ± 1.0 AU, %HRR = 88.1 ± 6.3, and ∆Blood lactate = 146.3 ± 87.9%; 30 minutes: session-RPE = 5.8 ± 1.9 AU, %HRR> = 83.3 ± 8.0, and ∆Blood lactate = 91.6 ± 39%) sessions. In conclusion, our findings suggest that session-RPE can be used in boxing training routines across a range of intensities and accurate measurements can be determined as early as 10 minutes after exercise. Key PointsIt is difficult to quantify and monitoring the external training load in martial arts (e.g. Aikido, Kung Fu, Judo) and physical combat sports (e.g. Boxing, Muay Thai), session RPE method appears to be a reliable method to quantifying training load in those sports.For many athletes it is impractical to wait 30 minutes after training session to provide a session-RPE. The present findings show that collecting ses-sion-RPE measures at 10 min following exercise ses-sions of various intensities (i.e. easy, moderate, and hard) provide similar values as if taken 30 min fol-lowing the session.Our data have significant practical benefit and fur-ther support the practical usefulness of session-RPE for measuring internal training load in sport.

3.
J Bodyw Mov Ther ; 39: 531-535, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38876680

RESUMEN

Body composition is a fundamental component of physical fitness related to the performance of Sitting volleyball (SV) players. Also, establishing the best method for evaluating the body composition of these para-athletes would be highly necessary for this field. The purpose of this study was (1) to describe the body composition of male and female highly trained SV players, (2) to compare the values obtained from this population by two different methods and (3) to establish validity on one of these methods. Thirteen Brazilian SV national team players (five males and eight females) participated in this study. The air-displacement plethysmography (ADP) method as the criterion assessment and the skinfolds (SF) method were conducted for each player. Results showed that there were no significant differences between the values of all players, which ADP and SF measured for body fat percentage (BF%) and body density (BD) (p > 0.05). We found significantly different values between male and female players for BF% by SF (p = 0.04) and BD by SF (p = 0.04). A high degree of reliability was found between ADP and SF measures for BF% and BD. There were statistically significant positive correlations between BF% and BD in all values for both methods (p < 0.01). This pilot study suggests that considering the magnitude of space, expense, and other limitations related to the ADP method against the SF method, we recommend using the SF method, which is a valid, viable and reliable method for measuring body composition in elite SV players.


Asunto(s)
Composición Corporal , Pletismografía , Grosor de los Pliegues Cutáneos , Voleibol , Humanos , Masculino , Femenino , Voleibol/fisiología , Proyectos Piloto , Composición Corporal/fisiología , Adulto Joven , Pletismografía/métodos , Reproducibilidad de los Resultados , Adulto , Sedestación
4.
Int J Exerc Sci ; 16(3): 513-524, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37622037

RESUMEN

Cell swelling caused by resistance training is proposed to provide an anabolic stimulus for muscle growth and it is believed that these effects are heightened with the use of low loads. The purpose of this study was to compare the acute effects of two volume-equated resistance training (RT) protocols, low-load (LL) versus high-load (HL), on elbow flexor muscles thickness, arm circumference, and blood lactate concentration in well-trained individuals. Eight resistance-trained males performed the following two RT protocols involving unilateral elbow flexion of the dominant arm: i) LL, four sets with 50% 1 repetition-maximum [1 RM] and ii) HL, ten sets with 85% 1 RM until failure, and equated volume. Pre- and post-session measurements included muscle thickness of the elbow flexors (biceps brachii and brachialis), upper arm circumference, and blood lactate concentration. Significant pre- to post-session increases were found in both protocols for muscle thickness (F (1, 28) = 11.74, p = 0.0019), and blood lactate (F (1, 28) = 35.55, p < 0.0001); no statistically significant differences were observed between conditions, however, the magnitude of increases favored LL. Significant between-condition differences favoring LL were observed for total repetitions (p = 0.007), time under tension (p = 0.007), and training density (p = 0.007). These results suggest that LL training promotes superior post-session increases in muscle thickness, indicating that RT protocols with longer times under tension and densities are beneficial when the goal is to promote acute cell swelling.

5.
J Sports Med Phys Fitness ; 62(2): 170-176, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33666073

RESUMEN

BACKGROUND: Isokinetic strength has been useful to assess muscle function related to sports and prevent injuries. The present study measured the isokinetic isometric and concentric shoulder rotators strength, agonist/antagonist ratio, and examined the relationships between isometric and concentric peak torque, and agonist/antagonist ratio in powerlifters compared to a control group. METHODS: The participants were divided into two groups: powerlifters group (N.=14) and physically active group (N.=9). Participants' were evaluated on isokinetic dynamometer for isometric, and concentric (two velocities, 60°/s and 180°/s) strength of shoulder external (ER) internal rotation (IR). Isometric contractions lasted 10 seconds, and concentric modes were 5 repetitions. RESULTS: Bilateral significant differences, between dominant and non-dominant side, were found in ER peak torque at isometric mode in powerlifters group (P=0.021). Powerlifters showed higher IR peak torque at isometric mode in dominant (P=0.040) and non-dominant side (P=0.014) than physically active group. Pearson correlations between isometric peak torque and concentric velocities ranged between 0.49 and 0.89 for powerlifters group, and between 0.73 and 0.93 for physically active group. For agonist/antagonist ratio, pearson correlation ranged between 0.47 and 0.83 for powerlifters group, and between 0.48 and 0.86 for physically active group. CONCLUSIONS: The bilateral differences in ER movement at isometric mode in powerlifters suggest that exercises for shoulder rotators must be included on training for joint safety and balance between sides despite isometric shoulder rotators strength in powerlifters was higher than physically active individuals. Results presented positive correlation between both muscle actions, isometric and concentric, in peak torque and agonist/antagonist ratio.


Asunto(s)
Articulación del Hombro , Hombro , Humanos , Contracción Isométrica , Músculos , Torque
6.
J Appl Biomech ; 27(4): 380-4, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21975179

RESUMEN

The aim of the current study was to investigate the EMG activity of pectoralis major and latissimus dorsi muscles during the pullover exercise. Eight healthy male volunteers took part in the study. The EMG activity of the pectoralis major and that of the latissimus dorsi of the right side were acquired simultaneously during the pullover exercise with a free-weight barbell during both the concentric and eccentric phases of the movement. After a warm-up, all the subjects were asked to perform the pullover exercise against an external load of 30% of their body weight, during 1 set × 10 repetitions. The criterion adopted to normalize the EMG data was the maximal voluntary isometric activation. The present findings demonstrated that the barbell pullover exercise emphasized the muscle action of the pectoralis major more than that of the latissimus dorsi, and the higher activation depended on the external force lever arm produced.


Asunto(s)
Dorso/fisiología , Movimiento/fisiología , Contracción Muscular/fisiología , Músculo Esquelético/fisiología , Entrenamiento de Fuerza/métodos , Tórax/fisiología , Adulto , Humanos , Masculino
7.
J Bodyw Mov Ther ; 25: 94-99, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33714518

RESUMEN

Hypopressive exercise (HE) has been contraindicated for people with cardiovascular disease because it involves isometric postures performed with low-pulmonary volume breath-holds, which are thought to increase blood pressure. The objective of this study was to analyze the hemodynamic responses to HE performed in the seated posture on systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and heart rate (HR) in normotensive females. Ten women (age = 31.2 ± 6.3 years) with previous experience in HE participated. Three sets of eight breathing cycles of HE breathing were completed. The HE breathing protocol consisted of three complete breathing cycles of controlled latero-costal inhalations and slow deep exhalations followed by a breath-hold and rib-cage expansion after every third exhalation. Measurements of SBP, DBP, MAP and HR were assessed at baseline, at the end of each set and at the end of minute 5, 10, 15 and 20 during the recovery period. The measurement of hemodynamic variables used a digital photoplethysmography device. Significant differences for SBP (baseline compared to SET2, p = 0.0182) and MAP (baseline compared to SET1, p = 0.0433; and SET2, p = 0.0072) were found. No significant differences were found in the recovery periods compared with baseline. Medium effect size for HR during REC5 (ES = 0.50) and REC10 (ES = 0.56) was observed. These findings indicate that HE in the seated posture performed by normotensive females leads to significant increases in SBP and MAP with no significant increase of HR and no hypotensive effect during recovery period. Our preliminary results should be supported by future randomized controlled trials.


Asunto(s)
Ejercicio Físico , Hipertensión , Presión Sanguínea , Niño , Femenino , Frecuencia Cardíaca , Hemodinámica , Humanos , Postura
8.
Exp Gerontol ; 146: 111245, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33476700

RESUMEN

AIM: The present study investigated whether hypertension, blood pressure, and antihypertensive therapy were associated with frailty status in community-dwelling older adults. In addition, we tested whether such associations were consistent across different frailty instruments. MATERIAL AND METHODS: Two-hundred older adults were enrolled in the study. Participant frailty status was determined according to a modified physical frailty phenotype (mFP), the FRAIL scale, and the Study of Osteoporotic Fracture (SOF) index. Blood pressure was assessed three times, in three different days, and mean values were used in the final analysis. Information pertaining to disease conditions and antihypertensive therapy were collected by two researchers through self-report and careful review of medical charts. RESULTS: No significant differences in hemodynamic parameters, hypertension diagnosis, and antihypertensive therapy were observed across frailty statuses, regardless of the frailty assessment tool used. CONCLUSION: Findings of the present study indicate that hypertension, blood pressure levels and antihypertensive medication were not cross-sectionally associated with frailty status in cognitively preserved community-dwelling older adults with low prevalence of comorbidities, regardless of the tool used for frailty identification.


Asunto(s)
Fragilidad , Hipertensión , Anciano , Antihipertensivos/uso terapéutico , Presión Sanguínea , Estudios Transversales , Anciano Frágil , Fragilidad/epidemiología , Evaluación Geriátrica , Humanos , Hipertensión/tratamiento farmacológico , Hipertensión/epidemiología , Vida Independiente , Prevalencia
9.
J Geriatr Phys Ther ; 44(2): E123-E131, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-31693536

RESUMEN

BACKGROUND AND PURPOSE: Cutoff points for physical function tests are commonly used in clinical practice for the evaluation, monitoring, and treatment of older adults. Previous studies have shown that, while age-related patterns of muscle strength change are similar between ethnic groups, strength values differ significantly independent of age. Whether the same applies to other physical function tests is presently unclear. This study investigated age- and gender-related changes of performance on a battery of physical function tests in Brazilian community dwellers. METHODS: The study followed a cross-sectional design. Participants were community-dwelling adults. Candidates were considered eligible if they were 18 years or older, lived independently, and possessed sufficient physical and cognitive abilities to perform all of the measurements required by the protocol. Physical function tests included isometric handgrip (IHG), 5 times sit-to-stand (5×STS) test, Timed Up and Go, 1-leg stance, and walking speed (WS) at usual and fast pace. RESULTS: Two-thousand eight-hundred and four people were enrolled. Mean age was 68.0 (7.0) years (range 50-102 years), and 2262 (80.7%) were women. Men displayed better IHG and balance, while women showed higher performance on the 5×STS and WS tests. A gender-specific pattern of decline in physical performance was observed. Specifically, women showed a linear age-dependent decline in all tests. In men, only in the IHG, 1-leg stance, and WS test at a fast pace was there a linear decline with age. In both genders, the lowest mean values of physical function tests were higher than the proposed cutoffs for sarcopenia. DISCUSSION AND CONCLUSIONS: Our findings indicate that the performance on different physical function tests decreases with advancing age in Brazilian adults, following a gender-specific pattern. In none of the tests did the lowest mean values reach the cutoffs for sarcopenia. This suggests that region-specific cutoffs might be necessary to identify older people at risk of adverse events.


Asunto(s)
Envejecimiento/fisiología , Disparidades en el Estado de Salud , Vida Independiente , Rendimiento Físico Funcional , Factores de Edad , Anciano , Anciano de 80 o más Años , Brasil , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales
10.
Mediators Inflamm ; 2010: 364290, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21234393

RESUMEN

In lymphocytes (LY), the well-documented antiproliferative effects of IFN-α are associated with inhibition of protein synthesis, decreased amino acid incorporation, and cell cycle arrest. However, the effects of this cytokine on the metabolism of glucose and glutamine in these cells have not been well investigated. Thus, mesenteric and spleen LY of male Wistar rats were cultured in the presence or absence of IFN-α, and the changes on glucose and glutamine metabolisms were investigated. The reduced proliferation of mesenteric LY was accompanied by a reduction in glucose total consumption (35%), aerobic glucose metabolism (55%), maximal activity of glucose-6-phosphate dehydrogenase (49%), citrate synthase activity (34%), total glutamine consumption (30%), aerobic glutamine consumption (20.3%) and glutaminase activity (56%). In LY isolated from spleen, IFNα also reduced the proliferation and impaired metabolism. These data demonstrate that in LY, the antiproliferative effects of IFNα are associated with a reduction in glucose and glutamine metabolisms.


Asunto(s)
Glucosa/metabolismo , Glutamina/metabolismo , Factores Inmunológicos/farmacología , Interferón-alfa/farmacología , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Animales , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Factores Inmunológicos/inmunología , Interferón-alfa/inmunología , Ganglios Linfáticos/citología , Linfocitos/citología , Masculino , Mesenterio/citología , Ratas , Ratas Wistar , Bazo/citología
11.
J Sports Med Phys Fitness ; 60(3): 395-401, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31684706

RESUMEN

BACKGROUND: Sitting volleyball (SV) is a popular Paralympic game, in which shoulders of SV players are overloaded continuously during play. Nevertheless, shoulder girdle muscle function has never been measured in this population yet. The objective of this study was to investigate the dominant and non-dominant strength profile of male and female elite SV players on a glenohumeral level. METHODS: A total of 13 Brazilian SV national team players volunteered to participate in this study (male: N.=6, age 32.8±4.1 years, body mass 83.2±19.4 kg, seated height 1.47±0.04 m; female: N.=7, age 32.8±4.1 years, body mass 80.1±17.9 kg, seated height 1.36±0.05 m). A Biodex dynamometer was used to measure internal rotation (IR) and external rotation (ER) of the glenohumeral muscle strength at 60°/s and 180°/s velocities in a concentric/concentric mode. RESULTS: It was observed that male SV players were stronger than the female players at both upper limbs. Concerning the side effects, significant differences were found for IR at 60°/s velocity (F=7.55, P=0.02) and ER at 180°/s velocity (F=5.91, P=0.03), with higher values on the dominant limb in comparison to the non-dominant limb for both the male and female players. There were significant gender differences for the IR inter-limb asymmetry at 180°/s velocity, with a greater asymmetry between both shoulders in the male players compared to the female players, preference for the dominant side in both groups. CONCLUSIONS: The SV players have an asymmetrical rotational strength profile. As muscular imbalance is a common injury pattern among overhead players. The findings of this study may assist the SV coaches and physiotherapists for evaluation and training of strength of the ER and IR shoulders of these players.


Asunto(s)
Músculo Esquelético/fisiología , Voleibol/fisiología , Adulto , Brasil , Femenino , Humanos , Masculino , Fuerza Muscular , Rotación , Articulación del Hombro/fisiología , Sedestación , Adulto Joven
12.
Nutrients ; 12(10)2020 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-32977714

RESUMEN

Frailty is a geriatric syndrome that refers to a state of reduced resiliency to stressful events that occurs in response to physiological and/or psychosocial detriments. Frailty is a predictor of poor prognosis, given that frail older adults are at higher risk of many adverse health-related events. Hence, the identification of potential strategies to prevent the development and progression of frailty is of extreme importance for avoiding its negative outcomes. An adequate protein consumption is advocated as a possible intervention for the management of frailty in older adults due to its effects on muscle mass and physical function. However, empirical evidence is still needed to support this proposition. On the other hand, substantial evidence from observational studies has provided important information on the association between frailty and dietary protein-related parameters. Here, we provide a narrative review of the current literature regarding the association between protein intake (amount (how much?), quality (what type?), and distribution across meals (when?)) and frailty-related parameters. The ultimate aim of this work is to offer practical, evidence-based indications to healthcare professionals responsible for the care of frail older adults.


Asunto(s)
Proteínas en la Dieta , Ingestión de Alimentos , Fragilidad/prevención & control , Anciano , Envejecimiento , Anciano Frágil , Evaluación Geriátrica , Humanos , Proteínas , Sarcopenia/prevención & control
13.
Nutrients ; 12(6)2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32492947

RESUMEN

The present study investigated and compared the patterns of dietary protein intake and physical function in Brazilian and Italian older women. Seventy-five Brazilian older women were recruited in a community senior center. Fifty-three age-matched Italian older women were selected from participants of the Longevity check-up (Lookup) 7+ study. In both samples, physical performance was evaluated by isometric handgrip strength (IHG) and five-time sit-to-stand (5 × STS) tests, while diet was assessed through 24-h recall. Results indicated that Brazilian women had a higher intake of plant-based protein (52.7% vs. 30.5% kcal), while Italian women consumed greater amounts of animal-derived protein (29.7% vs. 41.5% kcal). In Brazilian women, the binary logistic regression analysis indicated that body weight-adjusted protein consumption was associated with IHG adjusted by body mass index and with 5 × STS performance. In the Italian sample, the intake of isoleucine, leucine, and valine was significantly associated with 5 × STS performance. Our findings indicate that Brazilian and Italian community-dwelling older women show different patterns of protein intake, with higher consumption of plant-based protein in the Brazilian sample and higher ingestion of animal-derived protein in the Italian subgroup. These dietary patterns may differentially impact the relationship between physical function and protein intake observed in Brazilian and Italian older women.


Asunto(s)
Proteínas Dietéticas Animales/administración & dosificación , Ingestión de Alimentos/fisiología , Conducta Alimentaria/fisiología , Vida Independiente , Fenómenos Fisiológicos de la Nutrición/fisiología , Rendimiento Físico Funcional , Proteínas de Vegetales Comestibles/administración & dosificación , Factores de Edad , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Brasil , Femenino , Humanos , Isoleucina/administración & dosificación , Italia , Leucina/administración & dosificación , Longevidad , Valina/administración & dosificación
14.
Nutrients ; 12(2)2020 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-32079345

RESUMEN

The present study investigated the associations between frailty status and (a) daily protein intake, (b) daily body weight-adjusted protein intake, (c) branched-chain amino acid (BCAA) consumption, (d) evenness of protein distribution across main meals, (e) number of daily meals providing at least 30 g of protein, and (f) number of daily meals providing at least 0.4 g protein/kg of body weight in community-dwelling older adults. The relationship between frailty status and protein-related dietary parameters was explored across different frailty assessment tools. Two hundred older adults were enrolled in the study. Participant frailty status was determined according to a modified Fried's frailty phenotype (mFP), the FRAIL scale, and the Study of Osteoporotic Fracture (SOF) index. Diet was assessed by 24-h dietary recall, while diet composition was estimated using a nutritional software. A frailty instrument-dependent relationship was observed between frailty status and protein-related dietary parameters. Protein consumption was associated with frailty status only in participants identified as frail according to the mFP. In addition, protein and BCAA intake was found to be greater in robust and pre-frail participants relative to their frail counterparts. Our findings suggest that the association between frailty and protein-related dietary parameters is tool dependent. Specifically, protein and BCAA consumption appears to be lower only in older adults identified as frail by the mFP.


Asunto(s)
Dieta Saludable , Proteínas en la Dieta/administración & dosificación , Anciano Frágil/estadística & datos numéricos , Fragilidad/diagnóstico , Evaluación Geriátrica/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Aminoácidos de Cadena Ramificada/administración & dosificación , Estudios Transversales , Femenino , Fragilidad/dietoterapia , Evaluación Geriátrica/métodos , Humanos , Vida Independiente , Masculino , Persona de Mediana Edad , Evaluación Nutricional
15.
J Strength Cond Res ; 23(7): 2003-8, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19855324

RESUMEN

This study assessed the effect of different resistance exercise scheme (RES) designs of similar total of load lifted on the responses of testosterone, cortisol, and creatine kinase (CK). Twenty-seven healthy males performed 1 of 4 bench press workouts described by the 1 repetition maximum (1RM) load: 4 sets of maximum repetitions at 50%-1RM (50%-1RM RES), 5 sets of maximum repetitions at 75%-1RM (75%-1RM RES), 10 sets of maximum repetitions at 90%-1RM (90%-1RM RES), or 8 sets of maximum repetitions at 110%-1RM (110%-1RM RES). Each RES was equated by the total volume of load lifted (repetitions x sets x load). Blood samples, collected pre-exercise (Pre) and post-exercise (Post) at 1 and 24 hours (24 h), were analyzed for total and free testosterone, total cortisol, and CK. In general, testosterone and cortisol showed little change within or between the different RES (p > 0.05), possibly because of the relatively low volume lifted and/or the small muscle mass activated by the bench press exercise. Cortisol was elevated after the 75%-1RM RES at the Post sample, with this response also exceeding the other RES (p < 0.05). The 24 h CK response was also elevated after the 75%-1RM RES (p < 0.05), thereby suggesting greater training strain for the same volume of load. These results confirm previous recommendations regarding the prescription of resistance exercise and the importance of total volume as a stimulus for activating the endocrine system and achieving long-term adaptation.


Asunto(s)
Hidrocortisona/sangre , Entrenamiento de Fuerza , Testosterona/sangre , Levantamiento de Peso/fisiología , Adulto , Creatina Quinasa/sangre , Humanos , Masculino , Adulto Joven
16.
Exp Gerontol ; 127: 110715, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31473199

RESUMEN

Frailty is a potentially reversible state of increased vulnerability to negative health-related outcomes that occurs as a result of multisystem biological impairment and environmental aspects. Given the relevance of this condition in both clinics and research, biomarkers of frailty have been actively sought after. Although several candidate biomarkers of frailty have been identified, none of them has yet been incorporated in the assessment or monitoring of the condition. Over the last years, increasing research interest has been focused on myokines, a set of cytokines, small proteins and proteoglycan peptides that are synthetized, expressed and released by skeletal myocytes in response to muscular contractions. Myokines may act in autocrine, paracrine, and endocrine manner and regulate several processes associated with physical frailty, including muscle wasting, dynapenia, and slowness. This review discusses the rationale to support the use of myokines as biomarkers of frailty in older adults.


Asunto(s)
Citocinas/metabolismo , Fragilidad/diagnóstico , Músculo Esquelético/metabolismo , Anciano , Biomarcadores/metabolismo , Ejercicio Físico/fisiología , Femenino , Evaluación Geriátrica/métodos , Humanos , Masculino , Proteínas Musculares/fisiología , Debilidad Muscular/fisiopatología , Músculo Esquelético/fisiología , Sarcopenia/diagnóstico , Sarcopenia/fisiopatología
17.
Front Physiol ; 9: 1525, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30542289

RESUMEN

The present study aimed at investigating the effects of a daily undulating periodization (DUP) and non-periodized (NP) resistance training programs on hemodynamic parameters of older women. Forty-two older women were randomized into one of the three experimental groups: NP, DUP, and control group (CG). Evaluations of the hemodynamic parameters occurred before, during and after the intervention. The exercise programs were performed twice a week over 22 weeks. NP and DUP groups were based on 3 sets of 8-10 repetitions in 9 exercises. In NP, the two exercise sessions were based on traditional strength training, which was performed at a Difficult intensity according to the rating of perceived exertion (RPE) method. In DUP, the first session was based on power resistance exercise, in which the concentric muscle contraction was performed as fast as possible at a moderate intensity based on RPE, while the second session was the same that was performed by NP. The findings demonstrated that diastolic blood pressure (90.4 vs. 76.2 mmHg) and mean arterial pressure (108.6 vs. 92.7 mmHg) were significantly reduced after NP, while no significant alterations were observed in DUP. Nevertheless, both training groups seem to have a cardio protective effect, since both training modes prevented the increase in HR reported in the experimental period in CG. In conclusion, our findings indicate that a 22-week NP resistance training program causes beneficial effects on hemodynamic parameters of older women. Trial Registration: NCT03443375.

18.
PLoS One ; 13(12): e0208834, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30562370

RESUMEN

Resistance training (RT) is performed at distinct levels of intensity from the beginning to the end of exercise sets, increasing the sensation of effort as the exercise progress to more vigorous levels, commonly leading to changes on the facial expression of RT practitioners. The objective of this study is to evaluate changes in facial expressions using the Facial Action Coding System(FACS) and the activation of facial muscles by surface electromyography(sEMG) at two different levels of effort during resistance exercise and to investigate the correlation between facial expression and exercise intensity and fatigue. Eleven healthy male participants [23±6years; 1.77±6 m; 78±10kg] performed a set of arm curl exercise at 50% and 85% 1RM until muscle fatigue. The Surface electromyography (sEMG activity was recorded simultaneously in areas of the epicranius muscle (EM) and zygomatic major muscle (ZM). Facial expression was recorded and blindly scored by five experienced examiners. Scores (0-5) were based on the level of activity of the ZM (lip corner puller-Action Unit 12-FACS) during exercise. Facial expression and sEMG data were obtained during the exercise at the first repetition and at muscle failure. The root mean square (RMS) of the sEMG amplitude of the EM was significantly increased between the first and last repetition (50%1RM:p = 0.002,d = 1.75; and 85%1RM:p = 0.002,d = 1.54). The RMS values for the ZM were significantly increased between the first and last repetition (50%1RM:p<0.001,d = 2.67; 85%1RM:p<0.001,d = 0.50). The RMS values for the ZM were also increased in 85%1RM compared to values obtained from 50%1RM (p = 0.001,d = 1.12) at the first repetition. AU12 scores and RMS values were not statistically different between 85%1RM and 50%1RM at the last repetition. Furthermore, there was a strong correlation (r = 0.61;p = 0.045) between AU12 scores and the sEMG peak for the ZM. In conclusion, changes in facial expression may be directly correlated with different resistance exercise intensities and fatigue.


Asunto(s)
Expresión Facial , Músculos Faciales/fisiología , Fatiga Muscular/fisiología , Electromiografía , Humanos , Masculino , Persona de Mediana Edad
19.
Diabetol Metab Syndr ; 2: 31, 2010 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-20492685

RESUMEN

BACKGROUND: The effects of chronic aerobic exercise upon lipid profile has been previously demonstrated, but few studies showed this effect under resistance exercise conditions. OBJECTIVE: The aim of this study was to examine the effects of different resistance exercise loads on blood lipids. METHODS: Thirty healthy, untrained male volunteers were allocated randomly into four groups based at different percentages of one repetition maximum (1 RM); 50%-1 RM, 75%-1 RM, 90%-1 RM, and 110%-1 RM. The total volume (sets x reps x load) of the exercise was equalized. The lipid profile (Triglycerides [TG], HDL-cholesterol [HDL-c], LDL-cholesterol, and Total cholesterol) was determined at rest and after 1, 24, 48 and 72 h of resistance exercise. RESULTS: The 75%-1 RM group demonstrated greater TG reduction when compared to other groups (p < 0.05). Additionally, the 110%-1 RM group presented an increased TG concentration when compared to 50% and 75% groups (p = 0.01, p = 0.01, respectively). HDL-c concentration was significantly greater after resistance exercise in 50%-1 RM and 75%-1 RM when compared to 110%-1 RM group (p = 0.004 and p = 0.03, respectively). Accordingly, the 50%-1 RM group had greater HDL-c concentration than 110%-1 RM group after 48 h (p = 0.05) and 72 h (p = 0.004), respectively. Finally, The 50% group has showed lesser LDL-c concentration than 110% group after 24 h (p = 0.007). No significant difference was found in Total Cholesterol concentrations. CONCLUSION: These results indicate that the acute resistance exercise may induce changes in lipid profile in a specific-intensity manner. Overall, low and moderate exercise intensities appear to be promoting more benefits on lipid profile than high intensity. Long term studies should confirm these findings.

20.
J Sports Sci ; 27(5): 499-507, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19253084

RESUMEN

This study compared four different intensities of a bench press exercise for muscle soreness, creatine kinase activity, interleukin (IL)-1beta, IL-6, tumor necrosis factor-alpha (TNF-alpha), and prostaglandin E(2) (PGE(2)) concentrations in the blood. Thirty-five male Brazilian Army soldiers were randomly assigned to one of five groups: 50% one-repetition maximum (1-RM), 75% 1-RM, 90% 1-RM, 110% 1-RM, and a control group that did not perform the exercise. The total volume (sets x repetitions x load) of the exercise was matched among the exercise groups. Muscle soreness and plasma creatine kinase activity increased markedly (P < 0.05) after exercise, with no significant differences among the groups. Serum PGE(2) concentration also increased markedly (P < 0.05) after exercise, with a significantly (P < 0.05) greater increase in the 110% 1-RM group compared with the other groups. A weak but significant (P < 0.05) correlation was found between peak muscle soreness and peak PGE(2) concentration, but no significant correlation was evident between peak muscle soreness and peak creatine kinase activity, or peak creatine kinase activity and peak PGE(2) concentration. All groups showed no changes in IL-1beta, IL-6 or TNF-alpha. Our results suggest that the intensity of bench press exercise does not affect the magnitude of muscle soreness and blood markers of muscle damage and inflammation.


Asunto(s)
Mediadores de Inflamación/fisiología , Músculo Esquelético/fisiología , Dolor/fisiopatología , Esfuerzo Físico/fisiología , Levantamiento de Peso/fisiología , Adolescente , Brasil , Creatina Quinasa/sangre , Dinoprostona/sangre , Humanos , Mediadores de Inflamación/sangre , Interleucina-1beta/sangre , Interleucina-6/sangre , Masculino , Personal Militar , Dolor/diagnóstico , Dimensión del Dolor , Factor de Necrosis Tumoral alfa/sangre , Adulto Joven
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