RESUMEN
Background: Isometric training is used in sport, conventional physical activity and rehabilitation. Understandably, there is a great deal of research related to its effect on performance. It is known that the length of the muscle at the moment of contraction is a determinant of strength levels. In the literature we find research on isometric training in short muscle lengths, although it has not been studied in maximally shortened positions or the acute effects that occur after its application. Ballistic stretching (BS) is also popular in sport. Their execution involves actively reaching maximally shortened muscle positions. So far, isometric training has not been compared with protocols involving ballistic stretching. Considering the above, the aim of the present study was to investigate the effects of BS and voluntary isometric contraction at maximal shortening (VICAMS) on range of motion, strength and vertical jump. Methods: The study involved 60 healthy, physically active individuals (40 and 52 years old) who were randomly assigned to three groups: BS, VICAMS and a control group (CG). To assess acute effects, before and after the intervention, active range of motion (AROM), maximal voluntary isometric force (MVIF) and countermovement jump height (CMJ) were determined. Results: Time main effects and time*group interactions were found for all variables (p < 0.001). Between-group differences were shown for the VICAMS group after the intervention, with statistically significant higher AROM values compared to the other groups. MVIF values were also higher in the VICAMS group. Intra-group differences were observed for the VICAMS and Ballistic groups, as values on all variables increased from baseline. For the CMJ, intra-group differences showed that both the VICAMS and BS groups improved values compared to baseline values. Conclusions: The application of VICAMS induced acute improvements over BS in AROM, MVIF and CMJ. These results are important for coaches seeking immediate performance improvement and offer an optimal solution to the warm-up protocol.
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Contracción Isométrica , Fuerza Muscular , Ejercicios de Estiramiento Muscular , Rango del Movimiento Articular , Humanos , Contracción Isométrica/fisiología , Ejercicios de Estiramiento Muscular/fisiología , Masculino , Adulto , Fuerza Muscular/fisiología , Rango del Movimiento Articular/fisiología , Persona de Mediana Edad , Músculo Esquelético/fisiología , FemeninoRESUMEN
INTRODUCTION: This study aimed to investigate the effect of sex on regional and widespread pain sensitivity following acute bouts of stretching and to investigate the acute effect of stretching on regional and widespread pain sensitivity following stretching. METHODS: 73 healthy adults (36 females; mean age 25.6 ± 6.7 years) with an age range from 19 to 62 years were recruited for this experimental study. Regional and distant pain pressure pain thresholds, passive knee extension range of motion and passive resistive torque were measured before and 30 s after four bouts of 30-s static muscle stretching of the knee flexors with 20-s rest between bouts. RESULTS: No significant sex differences were found for pressure pain thresholds (p > 0.132), range of motion (p = 0.446) or passive resistive torque (p = 0.559) between pre-stretch and post-stretch measures. There were significant increases in pressure pain thresholds (p = 0.010), range of motion (p = 0.001) and passive resistive torque (p = 0.007) between pre-stretch and post-stretch measures. CONCLUSION: Muscle stretching significantly decreased regional and widespread pain sensitivity, indicating that central pain-modulating mechanisms are engaged during muscle stretching, resulting in stretch-induced hypoalgesia. Moreover, the results showed that the effect of stretching on regional and widespread pain sensitivity is not sex-specific.
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Ejercicios de Estiramiento Muscular , Umbral del Dolor , Rango del Movimiento Articular , Humanos , Adulto , Masculino , Femenino , Umbral del Dolor/fisiología , Ejercicios de Estiramiento Muscular/fisiología , Rango del Movimiento Articular/fisiología , Adulto Joven , Factores Sexuales , Persona de Mediana Edad , Torque , Músculo Esquelético/fisiología , Músculo Esquelético/fisiopatología , Articulación de la Rodilla/fisiología , Articulación de la Rodilla/fisiopatologíaRESUMEN
The 'StretchPole' foam roller product is mainly used to loosen muscle groups and joints in the deeper layers of the body that are normally inaccessible to the human hand, and to realign the skeletal structure by lying on the pole and performing exercises. It is also used to strengthen the core, which plays an important role in postural maintenance and stability. The purpose of this study was to determine the effects of the 'Solacon' exercise routine using a StretchPole on shoulder joint range of motion. Forty healthy participants performed Solacon exercises using a StretchPole. The specific method of Solacon comprises six movements: (1) chest slide, (2) crescent, (3) cone, (4) twister, (5) shoulder alternating rotation, and (6) chin-in exercise. The joint range of motion of the bilateral shoulder joint flexion, abduction, horizontal abduction, and external rotation (1st and 2nd) were measured before and after the exercises. All measures were significantly higher after exercise compared to before exercise. Solacon exercises improve thoracic spine and scapular mobility and stretch the anterior thoracic muscle groups. The shoulder joint in the broad sense consists of the humerus, scapula, clavicle, sternum, and ribs. These in turn constitute the scapulohumeral joint, acromioclavicular joint, sternoclavicular joint, scapulothoracic joint and functional second shoulder joint. In addition, costovertebral joints and intervertebral joints are also involved because of the added motion of the ribs and the spine. We considered that the ranges of motion of shoulder joint flexion, abduction, horizontal abduction, and external rotation measured in this study were expanded.
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Rango del Movimiento Articular , Articulación del Hombro , Humanos , Rango del Movimiento Articular/fisiología , Articulación del Hombro/fisiología , Masculino , Femenino , Adulto , Adulto Joven , Terapia por Ejercicio/métodos , Ejercicios de Estiramiento Muscular/fisiologíaRESUMEN
The mechanisms underlying range of motion enhancements via flexibility training discussed in the literature show high heterogeneity in research methodology and study findings. In addition, scientific conclusions are mostly based on functional observations while studies considering the underlying physiology are less common. However, understanding the underlying mechanisms that contribute to an improved range of motion through stretching is crucial for conducting comparable studies with sound designs, optimising training routines and accurately interpreting resulting outcomes. While there seems to be no evidence to attribute acute range of motion increases as well as changes in muscle and tendon stiffness and pain perception specifically to stretching or foam rolling, the role of general warm-up effects is discussed in this paper. Additionally, the role of mechanical tension applied to greater muscle lengths for range of motion improvement will be discussed. Thus, it is suggested that physical training stressors can be seen as external stimuli that control gene expression via the targeted stimulation of transcription factors, leading to structural adaptations due to enhanced protein synthesis. Hence, the possible role of serial sarcomerogenesis in altering pain perception, reducing muscle stiffness and passive torque, or changes in the optimal joint angle for force development is considered as well as alternative interventions with a potential impact on anabolic pathways. As there are limited possibilities to directly measure serial sarcomere number, longitudinal muscle hypertrophy remains without direct evidence. The available literature does not demonstrate the necessity of only using specific flexibility training routines such as stretching to enhance acute or chronic range of motion.
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Ejercicios de Estiramiento Muscular , Músculo Esquelético , Rango del Movimiento Articular , Humanos , Músculo Esquelético/fisiología , Ejercicios de Estiramiento Muscular/fisiología , Ejercicio de Calentamiento/fisiología , Sarcómeros/fisiología , Percepción del Dolor/fisiología , Adaptación Fisiológica , Tendones/fisiologíaRESUMEN
INTRODUCTION: The effects of stretching exercises on muscle strength have been widely researched in the literature, however, there are no studies investigating the effects of Pilates stretching. OBJECTIVE: To compare the effects of static stretching and Pilates stretching on the concentric muscle strength of the knee extensors and flexors. METHOD: 102 trained young adults were randomized into three groups: static stretching (n = 33); Pilates stretching (n = 34); control (n = 35). Isokinetic evaluation of the knee extensor and flexor muscles was performed at 60°/s and 180°/s, pre and post acute intervention with stretching. Interventions in the static stretching and Pilates stretching groups occurred in 3 sets x 30 s for each body region considered (a-knee extensor muscles; b-knee flexor muscles). The control group did not perform any intervention. RESULTS: No difference (p > 0.05) was observed between the groups after the intervention. There was only a significant intragroup improvement for the control group on the isokinetic muscle strength of the knee flexors at 180°/s, with a moderate effect size, considering the entire sample (p = 0.040; d = 0.42) and when considering only male gender (p = 0.010; d = 0.60). CONCLUSION: Static stretching or Pilates stretching performed as a warm-up did not impair or enhance the concentric muscle strength performance of the knee extensors and flexors. In this way, both forms of stretching can be considered as preparatory exercises before muscle strength training.
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Técnicas de Ejercicio con Movimientos , Fuerza Muscular , Ejercicios de Estiramiento Muscular , Músculo Esquelético , Humanos , Ejercicios de Estiramiento Muscular/fisiología , Masculino , Femenino , Fuerza Muscular/fisiología , Adulto Joven , Técnicas de Ejercicio con Movimientos/métodos , Músculo Esquelético/fisiología , Adulto , Rodilla/fisiología , Articulación de la Rodilla/fisiología , Rango del Movimiento Articular/fisiologíaRESUMEN
BACKGROUND: Conventional hamstring (HAM) stretching therapeutic effects are not substantiable in neuromusculoskeletal conditions with HAM tightness or shortness. We developed a kinetic chain stabilization exercise to provide a more sustainable effectiveness in adults with HAM tightness. However, its therapeutic effects and underlying motor mechanisms remain unknown. OBJECTIVE: To compare the effects of traditional active HAM stretching (AHS) and kinetic chain stretching (KCS) on electromyographic (EMG) amplitude and hip flexion range of motion (ROM) in participants with HAM tightness. METHODS: In this randomized controlled trial, 18 participants (mean age: 25.01 ± 2.47 years) with HAM tightness were assigned to the AHS or KCS group. Hip joint movement, EMG amplitude, and onset times were recorded in the bilateral erector spinae, HAM, transverse abdominis/internal oblique (IO), external oblique (EO), and rectus abdominis during a straight leg raise test. RESULTS: Compared to AHS, KCS led to greater increase in the hip flexion ROM and EMG activation amplitudes in the left and right EO and left IO. Post-test hip flexion ROM data in both the groups were higher than the pre-test data. CONCLUSION: KCS produced more sustainable effectiveness in hip flexion movement and EMG motor control patterns in participants with HAM tightness than AHS.
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Electromiografía , Músculos Isquiosurales , Ejercicios de Estiramiento Muscular , Rango del Movimiento Articular , Humanos , Adulto , Rango del Movimiento Articular/fisiología , Ejercicios de Estiramiento Muscular/fisiología , Masculino , Femenino , Músculos Isquiosurales/fisiología , Articulación de la Cadera/fisiología , Adulto JovenRESUMEN
ABSTRACT: Hamada, Y, Akasaka, K, Otsudo, T, Sawada, Y, Hattori, H, Kikuchi, Y, and Hall, T. Golfers' performance is improved more by combining foam rolling and dynamic stretch to the lead hip than practice golf swinging. J Strength Cond Res 38(7): e391-e397, 2024-Warming up is considered effective in improving performance and preventing injury. Despite this, there have been few studies investigating warm-up programs in golf and whether specific factors contribute to improved performance. The purpose of this study was to examine the immediate effects of combined foam rolling and dynamic stretch (FR + DS) to the lead hip on golf swing performance, hip range of motion (ROM), and muscle strength in amateur golfers using a randomized crossover design. The study sample comprised 22 men (mean ± SD ; age, 32.6 ± 8.5 years, body mass index (BMI), 23.4 ± 2.7 kg·m -2 ). Subjects were assigned to receive either FR + DS or repetitive golf swing practice (SW) before crossing over to the other intervention for another day. Measurements included golf swing performance (ball speed, club head speed, flight distance ["carry"], spin rate, and launch angle), hip internal rotation (IR), and external rotation (ER) ROM, as well as hip IR and ER muscle strength. Comparisons between groups were made before and after each intervention. For golf swing performance, FR + DS improved "carry" significantly more than SW ( p < 0.05). No significant differences in golf swing performance other than "carry" were found. In addition, IR ROM and IR muscle strength of the lead hip were significantly increased in the FR + DS group ( p < 0.05). FR + DS has effects on improving lead hip IR ROM and IR muscle strength, which may facilitate golfers' swing and "carry." FR + DS shows promise as a warm-up method for amateur golfers who want to improve golf performance.
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Rendimiento Atlético , Estudios Cruzados , Golf , Fuerza Muscular , Rango del Movimiento Articular , Humanos , Golf/fisiología , Masculino , Rendimiento Atlético/fisiología , Rango del Movimiento Articular/fisiología , Adulto , Fuerza Muscular/fisiología , Ejercicio de Calentamiento/fisiología , Cadera/fisiología , Adulto Joven , Ejercicios de Estiramiento Muscular/fisiología , Equipo Deportivo , Articulación de la Cadera/fisiologíaRESUMEN
ABSTRACT: Sasajima, S and Kubo, K. Effect of static stretching on tendon hysteresis and efficiency during repetitive jumping. J Strength Cond Res 38(6): 1041-1047, 2024-To date, no studies have experimentally shown a relationship between tendon hysteresis and exercise efficiency. However, previous studies showed that tendon hysteresis decreased immediately after static stretching. The purposes of this study were to (a) investigate the change in tendon hysteresis during the recovery period after static stretching and (b) determine whether exercise efficiency is enhanced because of the decline of tendon hysteresis after static stretching. For stretching (1 minute × 4 sets) and control conditions, tendon hysteresis was measured during ramp (i.e., lower strain rate of tendon) and ballistic (i.e., higher strain rate of tendon) contractions before, immediately, 15, 30, 45, and 60 minutes after interventions. In addition, electromyograms of the plantar flexor muscles (medial gastrocnemius [MG], lateral gastrocnemius [LG], and soleus muscles [SOL]) and oxygen consumption (VÌO 2 ) were measured during 10 minutes of submaximal repetitive jumping after both interventions. Tendon hysteresis (during ramp and ballistic contractions) reduced by static stretching persisted for up to 60 minutes (effect of time p < 0.001). During repetitive jumping, no differences in electromyograms of the plantar flexor muscles (effect of condition p = 0.786 for MG, p = 0.124 for LG, p = 0.682 for SOL) or VÌO 2 (effect of condition p = 0.534) were found between stretching and control conditions. These results suggest that the reduction in tendon hysteresis because of static stretching continues until 60 minutes after the end of stretching, and static stretching does not change the efficiency (evaluated by electromyograms of the plantar flexor muscles and VÌO 2 ) during submaximal repetitive jumping.
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Electromiografía , Ejercicios de Estiramiento Muscular , Músculo Esquelético , Consumo de Oxígeno , Tendones , Humanos , Ejercicios de Estiramiento Muscular/fisiología , Masculino , Adulto Joven , Tendones/fisiología , Músculo Esquelético/fisiología , Consumo de Oxígeno/fisiología , Adulto , Fenómenos Biomecánicos , Ejercicio Pliométrico , Contracción Muscular/fisiologíaRESUMEN
CONTEXT: Piriformis syndrome is often associated with muscle spasms and shortening of the piriformis muscle (PM). Physical therapy, including static stretching of the PM, is one of the treatments for this syndrome. However, the effective stretching position of the PM is unclear in vivo. This study aimed to determine the effective stretching positions of the PM using ultrasonic shear wave elastography. DESIGN: Observational study. METHODS: Twenty-one healthy young men (22.7 [2.4] y) participated in this study. The shear elastic modulus of the PM was measured at 12 stretching positions using shear wave elastography. Three of the 12 positions were tested with maximum internal rotation at 0°, 20°, or 40° hip adduction in 90° hip flexion. Nine of the 12 positions were tested with maximum external rotation at positions combined with 3 hip-flexion angles (70°, 90°, and 110°) and 3 hip-adduction angles (0°, 20°, and 40°). RESULTS: The shear elastic modulus of the PM was significantly higher in the order of 40°, 20°, and 0° of adduction and higher in external rotation than in internal rotation. The shear elastic modulus of the PM was significantly greater in combined 110° hip flexion and 40° adduction with maximum external rotation than in all other positions. CONCLUSION: This study revealed that the position in which the PM was most stretched was maximum external rotation with 110° hip flexion and 40° hip adduction.
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Diagnóstico por Imagen de Elasticidad , Ejercicios de Estiramiento Muscular , Músculo Esquelético , Humanos , Masculino , Adulto Joven , Ejercicios de Estiramiento Muscular/fisiología , Músculo Esquelético/fisiología , Músculo Esquelético/diagnóstico por imagen , Rango del Movimiento Articular/fisiología , Módulo de Elasticidad/fisiología , Adulto , Rotación , Articulación de la Cadera/fisiología , Articulación de la Cadera/diagnóstico por imagen , Síndrome del Músculo Piriforme/fisiopatología , Síndrome del Músculo Piriforme/terapia , Síndrome del Músculo Piriforme/diagnóstico por imagenRESUMEN
PURPOSE: This study compares the acute effects of a static stretching and a warmup protocol on the active and passive shear modulus of the hamstring muscles. METHODS: Muscle shear modulus was assessed at rest and during isometric contractions at 20â¯% of maximal voluntary isometric contraction (MVIC). RESULTS: After stretching, the passive shear modulus pattern was not altered, while at 20â¯% MVIC the biceps femoris short head (BFsh) and semimembranosus showed a shear modulus increase and decrease, respectively, which resulted on BFsh-SM pair differences (pre: 3.8⯱â¯16.8 vs. post: 39.3⯱â¯25.1â¯kPa; pâ¯<â¯0.001; dâ¯=â¯1.66) which was accompanied by a decrease of 18.3â¯% on MVIC. Following the warmup protocol, passive shear modulus remained unchanged, while active shear modulus was decreased for the semitendinosus (pre: 65.3⯱â¯13.5 vs. post: 60.3⯱â¯12.3â¯kPa; pâ¯=â¯0.035; dâ¯=â¯0.4). However, this difference was within the standard error of measurement (10.54â¯kPa), and did not impact the force production, since it increased only 1.4â¯% after the warmup. CONCLUSIONS: The results of this study suggest that the passive and active shear modulus responses of the individual hamstring muscles to static stretching are muscle-specific and that passive and active hamstring shear modulus are not changed by a standard warmup intervention.
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Músculos Isquiosurales , Contracción Isométrica , Ejercicios de Estiramiento Muscular , Ejercicio de Calentamiento , Humanos , Músculos Isquiosurales/fisiología , Ejercicios de Estiramiento Muscular/fisiología , Contracción Isométrica/fisiología , Masculino , Adulto Joven , Ejercicio de Calentamiento/fisiología , Adulto , Módulo de Elasticidad , UltrasonografíaRESUMEN
PURPOSE: We examined the effects of acute trunk stretching on central arterial stiffness and central and peripheral blood pressure in middle-aged to older adults. METHODS: Twenty-eight middle-aged to older adults (14M/14F, 72 ± 7 years, 28.5 ± 5.3 kg/m2) completed this randomized, controlled, crossover design trial. We measured carotid-femoral pulse wave velocity (cf-PWV) and central and peripheral blood pressures (BP) before and after a single bout of passively assisted trunk stretching (i.e., five rounds of six 30-s stretches) and a time-matched seated control visit (i.e., 30-min). Changes (Δ; post - pre) in cf-PWV and central and peripheral BP were compared between visits and sexes using separate linear mixed-effects models controlling for baseline values. RESULTS: Compared with seated control, central (systolic: - 3 ± 7 mmHg; diastolic: - 2 ± 5 mmHg) and peripheral (systolic: - 2 ± 8 mmHg; diastolic: - 1 ± 4 mmHg) BP were reduced following acute trunk stretching (ps ≤ 0.001). Between-visit differences for ∆cf-PWV (stretch: 0.09 ± 0.61 m/s; control: 0.37 ± 0.68 m/s, p = 0.038) were abolished when controlling for change in mean arterial pressure (∆MAP) (p = 0.687). The main effects of sex were detected for changes in systolic BPs (ps ≤ 0.029); more males (n = 13) saw BP reductions than females (n = 7). CONCLUSION: These findings demonstrate the superiority of acute trunk stretching over passive sitting of equated duration for BP in middle-aged to older adults, with an appreciable effect in males compared to females.
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Presión Sanguínea , Ejercicios de Estiramiento Muscular , Rigidez Vascular , Humanos , Masculino , Femenino , Rigidez Vascular/fisiología , Anciano , Presión Sanguínea/fisiología , Ejercicios de Estiramiento Muscular/fisiología , Persona de Mediana Edad , Torso/fisiología , Estudios Cruzados , Análisis de la Onda del PulsoRESUMEN
OBJECTIVES: Plantar fasciitis is a common problem in the foot region which has negative considerable impact on foot function. METHODS: In this parallel blinded randomized controlled trial, a total of thirty-seven subjects with plantar fasciitis (forty feet) were enrolled randomly to either the control group (stretching exercise) or the experimental group (stretching exercise plus dry needling). All interventions lasted six weeks and both groups were followed for two weeks. Primary outcomes were first step pain, pain, and activity daily function subscales of the FAOS questionnaire and secondary outcomes were plantar fascia thickness, and echogenicity. RESULTS: The mixed model ANOVAs showed significant group × time interactions for all primary outcomes. In both groups, first step pain and both subscales of the FAOS questionnaire were improved compared to baseline measurements. There were considerable differences between the two groups and the experimental group experienced more improvements in primary outcomes compared to the control group. For secondary outcomes, plantar fascia thickness at insertion significantly decreased, and the echogenicity in the two regions significantly increased in the experimental group compared to the control group. CONCLUSION: These results suggest that the combination of dry needling and stretching exercises can be an effective conservative treatment for plantar fasciitis subjects.
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Punción Seca , Fascitis Plantar , Ejercicios de Estiramiento Muscular , Humanos , Fascia/diagnóstico por imagen , Fascitis Plantar/complicaciones , Fascitis Plantar/diagnóstico por imagen , Fascitis Plantar/terapia , Dolor/etiología , Dimensión del Dolor/métodos , Resultado del Tratamiento , Ultrasonografía , Ejercicios de Estiramiento Muscular/fisiología , Pie/diagnóstico por imagen , Método Simple Ciego , Tratamiento ConservadorRESUMEN
PURPOSE: The current study compared the local and systemic vascular responsiveness after small muscle mass endurance training or passive stretching training (PST). METHODS: Thirty-six sex-matched healthy participants underwent 8-wk single-leg knee extension (SLKE) (n = 12) training or PST (n = 12), or no intervention (control, n = 12). Before and after the intervention, local and systemic vascular responsiveness was assessed by Doppler ultrasound at the femoral (local effect) and brachial artery (systemic effect) during single passive leg movement and brachial flow-mediated dilation (FMD) test, respectively. RESULTS: After training, delta femoral blood flow (representing the local vascular responsiveness) increased after SLKE and PST by +54 (7)% (effect size, 2.72; P < 0.001) and +20 (2)% (effect size, 2.43; P < 0.001), respectively, albeit with a greater extent in SLKE (post-SLKE vs post-PST: +56 [8]% [effect size, 2.92; P < 0.001]). Interestingly, the %FMD (standing for the systemic effect) increased after SLKE and PST by +12 (2)% (effect size, 0.68; P < 0.001) and +11 (1)% (effect size, 0.83; P < 0.001), respectively, without any between-groups difference (P > 0.05). No changes occurred in control. CONCLUSIONS: The present findings revealed that both active and passive training modalities induced similar improvements in the brachial artery dilatation capacity, whereas the former was more effective in improving femoral artery blood flow. Passive stretching could be used in people with limited mobility to improve vascular responsiveness both at the local and systemic level and in this latter case has similar effects as small muscle mass endurance training.
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Arteria Braquial/fisiología , Entrenamiento Aeróbico/métodos , Arteria Femoral/fisiología , Ejercicios de Estiramiento Muscular/fisiología , Flujo Sanguíneo Regional/fisiología , Adulto , Femenino , Voluntarios Sanos , Humanos , Extremidad Inferior/irrigación sanguínea , Masculino , Adulto JovenRESUMEN
The purpose of the present study was to examine the association between static stretching load and changes in the flexibility of the hamstrings. Twelve healthy men received static stretching for 60 s at two different intensities based on the point of discomfort (100%POD and 120%POD intensity), in random order. To assess the flexibility of the hamstrings, the knee extension range of motion (ROM). Passive torque at end ROM, and muscle-tendon unit stiffness were measured before and after stretching. The static stretching load was calculated from the passive torque throughout static stretching. The knee extension ROM and passive torque at end ROM increased in both intensities (p < 0.01). The muscle-tendon unit stiffness decreased only in the 120%POD (p < 0.01). There were significant correlations between the static stretching load and the relative changes in the knee extension ROM (r = 0.56, p < 0.01) and muscle-tendon unit stiffness (r = - 0.76, p < 0.01). The results suggested that the static stretching load had significant effects on changes in the knee extension ROM and muscle-tendon unit stiffness of the hamstrings, and high-intensity static stretching was useful for improving the flexibility of the hamstrings because of its high static stretching load.
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Músculos Isquiosurales/fisiología , Ejercicios de Estiramiento Muscular/fisiología , Humanos , Masculino , Rango del Movimiento Articular , Adulto JovenRESUMEN
OBJECTIVES: The purpose of this study was to examine the time course of changes in the range of motion and muscle-tendon unit stiffness of the hamstrings after two different intensities of static stretching. METHODS: Fourteen healthy men (20.9 ± 0.7 years, 169.1 ± 7.5cm, 61.6 ± 6.5kg) received static stretching for 60 seconds at two different intensities based on the point of discomfort (100%POD and 120%POD) of each participant, in random order. To evaluate the time course of changes in the flexibility of the hamstrings, the knee extension range of motion (ROM), passive torque at end ROM, and muscle-tendon unit stiffness were measured pre-stretching, post-stretching, and at both 10 and 20 minutes after static stretching. RESULTS: For both intensities, ROM and passive torque at pre-stretching were significantly smaller than those at post-stretching (p < 0.01 in both intensities), 10 minutes (p < 0.01 in both intensities), and 20 minutes (p < 0.01 in both intensities). The muscle-tendon unit stiffness at pre-stretching was significantly higher than that at post-stretching (p < 0.01), 10 minutes (p < 0.01), and 20 minutes (p < 0.01) only in the 120%POD, but it showed no change in the 100%POD. CONCLUSION: The results showed that ROM and passive torque increased in both intensities, and the effects continued for at least 20 minutes after stretching regardless of stretching intensity. However, the muscle-tendon unit stiffness of the hamstrings decreased only after static stretching at the intensity of 120%POD, and the effects continued for at least 20 minutes after stretching.
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Fuerza Muscular/fisiología , Ejercicios de Estiramiento Muscular/fisiología , Rango del Movimiento Articular/fisiología , Tendones/fisiología , Músculos Isquiosurales , Humanos , Rodilla , Masculino , Movimiento (Física) , Torque , Adulto JovenRESUMEN
The current study aimed to verify whether or not passive static stretching affects balance control capacity. Thirty-eight participants (19 women and 19 men) underwent a passive static stretching session, involving the knee extensor/flexor and dorsi/plantarflexor muscles, and a control session (no stretching, CTRL). Before (PRE), immediately after (POST), after 15 (POST15) and 30 min (POST30) from stretching (or rest in CTRL), balance control was evaluated under static and dynamic conditions, with open/closed eyes, and with/without somatosensory perturbation (foam under the feet). During tests, centre of pressure (CoP) sway area and perimeter and antero-posterior and medio-lateral sway mean speed were computed. Surface electromyography root mean square (sEMG RMS) was calculated from the vastus lateralis, biceps femoris, gastrocnemius medialis, and tibialis anterior muscles during MVC and during the balance tests. Hip flexion/extension and dorsi/plantarflexion range of motion (ROM), maximum voluntary contraction (MVC) and sEMG RMS during MVC were measured at the same time points. After stretching, ROM increased (≈6.5%; P<0.05), while MVC and sEMG RMS decreased (≈9% and ≈7.5%, respectively; P<0.05). Regardless of the testing condition, CoP sway area and the perimeter remained similar, while antero-posterior and medio-lateral sway mean speed decreased by ≈8% and ≈12%, respectively (P<0.05). sEMG RMS during the balance tests increased in all muscles in POST (≈7%, P<0.05). All variables recovered in POST30. No changes occurred in CTRL. Passive static stretching did not affect the overall balance control ability. However, greater muscle activation was required to maintain similar CoP sway, thus suggesting a decrease in muscle efficiency.
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Contracción Muscular/fisiología , Ejercicios de Estiramiento Muscular/fisiología , Músculo Esquelético/diagnóstico por imagen , Equilibrio Postural/fisiología , Adulto , Electromiografía/métodos , Femenino , Pie/diagnóstico por imagen , Pie/fisiología , Humanos , Rodilla/diagnóstico por imagen , Rodilla/fisiología , Pierna/diagnóstico por imagen , Pierna/fisiología , Masculino , Músculo Esquelético/fisiología , Rango del Movimiento Articular/fisiologíaRESUMEN
INTRODUCTION: This study examined the effects of 24 wk of daily static stretching of the plantarflexors (unilateral 4 × 60-s stretching, whereas the contralateral leg served as a control; n = 26) on joint range of motion (ROM), muscle-tendon unit morphological and mechanical properties, neural activation, and contractile function. METHODS: Torque-angle/velocity was obtained in passive and active conditions using isokinetic dynamometry, whereas muscle-tendon morphology and mechanical properties were examined using ultrasonography. RESULTS: After the intervention, ROM increased (stretching, +11° ± 7°; control, 4° ± 8°), and passive torque (stretching, -10 ± 11 N·m; control, -7 ± 10 N·m) and normalized EMG amplitude (stretching, -3% ± 6%; control, -3% ± 4%) at a standardized dorsiflexion angle decreased. Increases were seen in passive tendon elongation at a standardized force (stretching, +1.3 ± 1.6 mm; control, +1.4 ± 2.1 mm) and in maximal passive muscle and tendon elongation. Angle of peak torque shifted toward dorsiflexion. No changes were seen in tendon stiffness, resting tendon length, or gastrocnemius medialis fascicle length. Conformable changes in ROM, passive dorsiflexion variables, tendon elongation, and angle of peak torque were observed in the nonstretched leg. CONCLUSIONS: The present findings indicate that habitual stretching increases ROM and decreases passive torque, altering muscle-tendon behavior with the potential to modify contractile function.
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Contracción Muscular/fisiología , Ejercicios de Estiramiento Muscular/fisiología , Músculo Esquelético/fisiología , Rango del Movimiento Articular/fisiología , Electromiografía , Femenino , Humanos , Masculino , Músculo Esquelético/diagnóstico por imagen , Ultrasonografía , Adulto JovenRESUMEN
The aim of this study was to determine whether the first sensation of stretching (ROMFSS) may predict the maximum range of motion (ROMMAX) in male (N = 37) and female (N = 32) volunteer subjects, and to assess the reliability of the ROM perceived by subjects in relation to a pre-determined ROM (ROM50%). Subjects attempted three experimental sessions with 48 hours between sessions 1 and 2 and 28 days between sessions 1 and 3. Within each session, five trials were performed with isokinetic equipment to assess posterior thigh muscle flexibility. The results revealed a strong and significant correlation between ROMMAX and ROMFSS for both sexes, females (r = 0.96, p < 0.001, R2 = 0.92) and males (r = 0.91, p < 0.001; R2 = 0.82). The accuracy of the model verified by the standard error of estimate (SEE) was high in the equations proposed for both female (SEE = 4.53%) and male (SEE = 5.45%). Our results revealed that ROMFSS may predict the ROMMAX for both male and female subjects. The ROMFSS may contribute to the development of evaluation methods that do not subject the individuals to conditions that may include unnecessary risk of injury and is well suited to monitor the training process of stretching exercises with submaximal loads.
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Ejercicios de Estiramiento Muscular/fisiología , Músculo Esquelético/fisiología , Sensación/fisiología , Femenino , Humanos , Masculino , Músculo Esquelético/lesiones , Percepción/fisiología , Factores de Riesgo , MusloRESUMEN
Although it is well known that both stretching and foam rolling can acutely increase the range of motion (ROM) and affect performance, the effects of a combined treatment (foam rolling and stretching) are not yet clear. Hence, the purpose of this meta-analysis was to compare the combined effect to that of stretching or foam rolling alone on both ROM and performance. We assessed the effect of a combined treatment on ROM and compared it to the effect of stretching, foam rolling, and a control condition by applying a random-effect meta-analysis. We also applied the same model to compare the effect of the combined treatment on performance. Moreover, by applying a mixed-effect model, we performed subgroup analyses with the stretching technique, type of foam rolling, tested muscles, type of task, and the order of the combined treatment. We found a significant overall effect on ROM change when comparing the combined treatment with the control condition (effect size (ES) = -0.332); however, no significant effect was found when comparing it to stretching (ES = 0.032) or foam rolling alone (ES = -0.225). The meta-analysis revealed no significant overall effect on performance when the combined treatment was compared to stretching alone (ES = -0.029). However, the subgroup analysis for performance revealed a superior effect for the combined treatment compared to stretching alone, but only if foam rolling was followed by stretching (ES = -0.17), and not vice versa. Athletes do not have to combine stretching with foam rolling since no additional effect was observed. However, to increase performance, the combination of foam rolling followed by stretching can lead to greater improvements.
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Rendimiento Atlético/fisiología , Ejercicios de Estiramiento Muscular/fisiología , Rendimiento Físico Funcional , Equipo Deportivo , Ejercicio de Calentamiento/fisiología , Adulto , Femenino , Humanos , Masculino , Músculo Esquelético/fisiología , Rango del Movimiento Articular , Adulto JovenRESUMEN
Stretching is commonly used to increase range of motion and flexibility. Therefore, investigations are usually oriented towards the muscle-tendon unit. Limited evidence exists regarding potential effects of stretching on peripheral nerves which lie within muscles. The objective of this investigation will be to elucidate the responses of peripheral nerves to stretching. A literature search was performed using the following databases: Scopus, NLM Pubmed and ScienceDirect. Studies regarding the effects of stretching protocols on responses of peripheral nerves were retrieved for investigation. The NHLBI tool was used for quality assessment. Outcomes included nerve stiffness, nerve displacement, pain pressure thresholds and resistive torque. A total of 10 studies were considered eligible and were included in this investigation. The quality assessment of the studies revealed an overall "fair to good" methodological quality across the included studies. All studies except for one involved healthy participants. High heterogeneity of stretching protocols was retrieved. As a consequence of stretching, nerve stiffness (-15.6%) and pain pressure thresholds (-1.9kg) increased. Nerve displacements on each movement plane for all the considered nerves and nerve deformation were also frequently observed. Peripheral nerve responses to muscle stretching include decreased nerve stiffness and increased pain pressure thresholds. Nerve displacement also frequently occurs. It is still unclear if reduced nerve displacement may lead to clinical outcomes. There is a lack of longitudinal studies regarding peripheral nerve adaptations to stretching.