Effect of a 4-week static stretching program for plantar flexor muscles on physical performance and muscle properties

BACKGROUND: The effects of a long-term static stretching program on physical performance parameters have not been elucidated completely, although the effects on muscle flexibility have a consensus. OBJECTIVE: This study aimed to investigate the effect of a long-term static stretching program on physical performance and muscle properties. METHODS: Participants performed a 2-min static stretching for the ankle joint 5 times per week for 4 weeks. Physical performance and muscle properties was measured before and after the static stretching program. RESULTS: Results showed that range of motion (ROM), dynamic postural stability, and muscle hardness were positively changed, whereas other variables i.e. maximal isometric plantar flexion moment, jump heights, muscle-tendon junction displacement and its angle, were not. CONCLUSIONS: Four-week of SS program may improve ROM, dynamic postural stability, and muscle hardness without decreasing physical performance.

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Protein Intake and Physical Performance Following Long-Term Stay on the International Space Station

Aerospace Medicine and Human Performance ◽

10.3357/amhp.5640.2021 ◽

2021 ◽

Vol 92 (3) ◽

pp. 153-159

Author(s):

Yuko Nozawa ◽

Yukiko Wagatsuma

Keyword(s):

Physical Performance ◽

Protein Intake ◽

Plantar Flexion ◽

Space Station ◽

Knee Extension ◽

Carbohydrate Intake ◽

International Space ◽

Exercise Effect ◽

Ankle Plantar Flexion

INTRODUCTION: Exposure to microgravity reduces muscle mass, volume, and performance. The ingestion of protein, especially combined with carbohydrate intake and exercise after ingestion, improves net muscle protein synthesis and increases muscle mass. However, there are few studies on this relationship during and after a long-term spaceflight. The objective of this study was to investigate the influence of protein and the combined effects of carbohydrate intake on muscle performance following long-term spaceflight.METHODS: This study is a retrospective cohort study involving secondary analysis of data stored in the NASA Lifetime Surveillance of Astronaut Health Repository. Multivariable analysis was performed to evaluate the impact of protein intake on physical performance by considering covariates potentially associated with each model.RESULTS: After adjusting for sex, age, flight week, energy intake, and preflight physical performance, protein intake was found to be significantly associated with concentric measurements for knee extension ( 51.66), ankle plantar flexion ( 32.86), and eccentric measurements for ankle plantar flexion ( 79.85) at 5 d after landing. Significant associations remained after controlling for exercise effect. No significant interaction between protein and carbohydrate intake was observed in either model.DISCUSSION: Protein intake during spaceflight was related to physical performance for knee extension and ankle plantar flexion, even after taking exercise effect into consideration. However, protein and carbohydrate intake provided no synergetic benefit. This suggests that high protein intake, about twice the current average intake, may serve as a countermeasure to offset the negative effects of long-duration spaceflights.Nozawa Y, Wagatsuma Y. Protein intake and physical performance following long-term stay on the International Space Station. Aerosp Med Hum Perform. 2021; 92(3):153159.

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Intrinsic foot muscle hardness is related to dynamic postural stability after landing in healthy young men

Gait & Posture ◽

10.1016/j.gaitpost.2021.03.005 ◽

2021 ◽

Vol 86 ◽

pp. 192-198 ◽

Cited By ~ 1

Author(s):

Noriaki Maeda ◽

Arisu Hirota ◽

Makoto Komiya ◽

Masanori Morikawa ◽

Rami Mizuta ◽

...

Keyword(s):

Postural Stability ◽

Young Men ◽

Muscle Hardness ◽

Dynamic Postural Stability ◽

Intrinsic Foot Muscle

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Influence of static stretching on viscoelastic properties of human tendon structures in vivo

Journal of Applied Physiology ◽

10.1152/jappl.2001.90.2.520 ◽

2001 ◽

Vol 90 (2) ◽

pp. 520-527 ◽

Cited By ~ 206

Author(s):

Keitaro Kubo ◽

Hiroaki Kanehisa ◽

Yasuo Kawakami ◽

Tetsuo Fukunaga

Keyword(s):

Viscoelastic Properties ◽

Plantar Flexion ◽

Maximum Voluntary Contraction ◽

Voluntary Contraction ◽

Medial Gastrocnemius ◽

Static Stretching ◽

Tendon Elongation ◽

Before And After ◽

Human Tendon

The purpose of this study was to investigate the influences of static stretching on the viscoelastic properties of human tendon structures in vivo. Seven male subjects performed static stretching in which the ankle was passively flexed to 35° of dorsiflexion and remained stationary for 10 min. Before and after the stretching, the elongation of the tendon and aponeurosis of medial gastrocnemius muscle (MG) was directly measured by ultrasonography while the subjects performed ramp isometric plantar flexion up to the maximum voluntary contraction (MVC), followed by a ramp relaxation. The relationship between the estimated muscle force (Fm) of MG and tendon elongation ( L) during the ascending phase was fitted to a linear regression, the slope of which was defined as stiffness of the tendon structures. The percentage of the area within the Fm- L loop to the area beneath the curve during the ascending phase was calculated as an index representing hysteresis. Stretching produced no significant change in MVC but significantly decreased stiffness and hysteresis from 22.9 ± 5.8 to 20.6 ± 4.6 N/mm and from 20.6 ± 8.8 to 13.5 ± 7.6%, respectively. The present results suggest that stretching decreased the viscosity of tendon structures but increased the elasticity.

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Teacrine Does Not Enhance Physical Performance or Training Status Over 8 Weeks

10.21203/rs.3.rs-429804/v1 ◽

2021 ◽

Author(s):

Henrique Santa Capita Cerqueira ◽

Hugo Tourinho Filho ◽

Marcos Corrêa Junior ◽

Carlos Eduardo Martinelli Junior

Keyword(s):

Side Effects ◽

Physical Performance ◽

Training Status ◽

Training Performance ◽

Igf I ◽

Before And After ◽

Physical Tests ◽

The Individual ◽

Igfbp 3

Abstract Background: Fatigue is a condition that may affect physical performance during training sessions. Consequently, this will impact training performance, moreover in the performance of the individual in long-term. Caffeine is broadly utilized to this purpose, however contains several side effects. Thus, teacrine emerges as an alternative to the use of caffeine, providing the same benefits without the side effects. Thus, the current work had as an objective to investigate the effects of 8 weeks of supplementation with teacrine on physical performance and the training status of young amateur athletes. Methods: 22 subjects were divided into two groups – Teacrine Group (T) and Placebo Group (P) – and evaluated before and after the intervention period. Evaluations included physical tests and hormonal doses of IGF-I and IGFBP-3, utilized as markers of training status. Results: Results demonstrated that teacrine was not capable of promoting benefits in relation to physical performance of the subjects. Neither produced effects on serum secretion of IGF-I and its binding protein, IGFBP-3.Conclusion: Therefore, the findings of the present study do not support the use of teacrine for the purpose of increasing physical performance.

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Dynamic Postural Stability and Hearing Preservation after Cochlear Implantation

Audiology and Neurotology ◽

10.1159/000494247 ◽

2018 ◽

Vol 23 (4) ◽

pp. 222-228

Author(s):

Christof Buhl ◽

Dmitri Artemiev ◽

Flurin Pfiffner ◽

Jaap Swanenburg ◽

Dorothe Veraguth ◽

...

Keyword(s):

Cochlear Implantation ◽

Postural Stability ◽

Pure Tone ◽

Hearing Preservation ◽

Residual Hearing ◽

Significant Difference ◽

Before And After ◽

The Mean ◽

Functional Gait ◽

Dynamic Postural Stability

Objectives: (1) To assess dynamic postural stability before and after cochlear implantation using a functional gait assessment (FGA). (2) To evaluate the correlation between loss of residual hearing and changes in dynamic postural stability after cochlear implantation. Methods: Candidates for first-sided cochlear implantation were prospectively included. The FGAs and pure-tone audiograms were performed before and 4–6 weeks after cochlear implantation. Results: Twenty-three subjects were included. Forty-eight percent (n = 11) showed FGA performance below the age-referenced norm before surgery. One subject had a clinically relevant decrease of the FGA score after cochlear implantation. No significant difference between the mean pre- and postoperative FGA scores was detectable (p = 0.4). Postoperative hearing loss showed no correlation with a change in FGA score after surgery (r = 0.3, p = 0.3, n = 16). Conclusion: Single-sided cochlear implantation does not adversely affect dynamic postural stability 5 weeks after surgery. Loss of functional residual hearing is not correlated with a decrease in dynamic postural stability.

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Long-term effects of robotic hippotherapy on dynamic postural stability in cerebral palsy

Computer Assisted Surgery ◽

10.1080/24699322.2016.1240297 ◽

2016 ◽

Vol 21 (sup1) ◽

pp. 111-115 ◽

Cited By ~ 1

Author(s):

Young Joo Cha ◽

Megan Stanley ◽

Tim Shurtleff ◽

Joshua (Sung) H. You

Keyword(s):

Cerebral Palsy ◽

Postural Stability ◽

Long Term Effects ◽

Dynamic Postural Stability

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Reliability and usefulness of the single leg heel raise balance test in patients with chronic ankle instability

Scientific Reports ◽

10.1038/s41598-021-99466-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jin Hyuck Lee ◽

Hae Woon Jung ◽

Taek Sung Jung ◽

Woo Young Jang

Keyword(s):

Postural Stability ◽

Ankle Instability ◽

Significant Risk ◽

Significant Risk Factor ◽

Chronic Ankle Instability ◽

Muscle Endurance ◽

Healthy Controls ◽

Balance Test ◽

Before And After ◽

Dynamic Postural Stability

AbstractWe aimed to analyze the differences in static (including conventional and modified [single-leg heel-raise balance]) and dynamic postural stability and muscle endurance between patients with chronic ankle instability (CAI) and healthy controls, and to determine the reliability and usefulness of the single-leg heel-raise balance test in patients with CAI. In total, 26 patients with CAI and 26 healthy controls were enrolled. Postural stability was assessed using a postural stabilometry system. Muscle endurance was measured in dorsiflexion and plantarflexion using an isokinetic device. Modified static postural stability (P < 0.001) and dynamic postural stability (P < 0.001) were significantly poorer in the affected ankles of patients with CAI than in the controls. Plantarflexion endurance was significantly lower in the affected ankles of the patients with CAI than in the controls (P = 0.023). Modified static postural stability significantly correlated with plantarflexion endurance in both groups (CAI group: r = − 0.470, P = 0.015; healthy controls group: r = − 0.413, P = 0.036). Plantarflexion endurance was a significant risk factor for modified static postural stability in both the CAI group (R2 = 0.221, P = 0.015) and healthy controls (R2 = 0.170, P = 0.036). Given the reliability of the modified static postural stability test, clinicians and therapists should consider using it to assess improvements in postural stability and muscle endurance in patients with CAI before and after rehabilitation.

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Dynamic Postural-Stability Deficits After Cryotherapy to the Ankle Joint

Journal of Athletic Training ◽

10.4085/1062-6050-50.7.07 ◽

2015 ◽

Vol 50 (9) ◽

pp. 893-904 ◽

Cited By ~ 6

Author(s):

Karl Fullam ◽

Brian Caulfield ◽

Garrett F. Coughlan ◽

Mark McGroarty ◽

Eamonn Delahunt

Keyword(s):

Ankle Joint ◽

Postural Stability ◽

Sagittal Plane ◽

Center Of Pressure ◽

Mean Velocity ◽

Balance Test ◽

Before And After ◽

Elite Level ◽

Star Excursion Balance Test ◽

Dynamic Postural Stability

Context Decreased postural stability is a primary risk factor for lower limb musculoskeletal injuries. During athletic competitions, cryotherapy may be applied during short breaks in play or during half-time; however, its effects on postural stability remain unclear. Objective To investigate the acute effects of a 15-minute ankle-joint cryotherapy application on dynamic postural stability. Design Controlled laboratory study. Setting University biomechanics laboratory. Patients or Other Participants A total of 29 elite-level collegiate male field-sport athletes (age = 20.8 ± 1.12 years, height = 1.80 ± 0.06 m, mass = 81.89 ± 8.59 kg) participated. Intervention(s) Participants were tested on the anterior (ANT), posterolateral (PL), and posteromedial (PM) reach directions of the Star Excursion Balance Test before and after a 15-minute ankle-joint cryotherapy application. Main Outcome Measure(s) Normalized reach distances; sagittal-plane kinematics of the hip, knee, and ankle joints; and associated mean velocity of the center-of-pressure path during performance of the ANT, PL, and PM reach directions of the Star Excursion Balance Test. Results We observed a decrease in reach-distance scores for the ANT, PL, and PM reach directions from precryotherapy to postcryotherapy (P < .05). No differences were observed in hip-, knee-, or ankle-joint sagittal-plane kinematics (P > .05). We noted a decrease in mean velocity of the center-of-pressure path from precryotherapy to postcryotherapy (P < .05) in all reach directions. Conclusions Dynamic postural stability was adversely affected immediately after cryotherapy to the ankle joint.

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Recovery of Posture Stability at Different Foot Placements in Patients Who Underwent Minimally Invasive Total Hip Arthroplasty: A One-Year Follow-Up Study

BioMed Research International ◽

10.1155/2015/463792 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

Chun-Ju Chang ◽

Na-Ling Lin ◽

Mel S. Lee ◽

Jen-Suh Chern

Keyword(s):

Total Hip Arthroplasty ◽

Minimally Invasive ◽

Functional Capacity ◽

Hip Arthroplasty ◽

Postural Stability ◽

Rehabilitation Program ◽

Total Hip ◽

Before And After ◽

One Year

To understand the progression of recovery in postural stability and physical functioning after patients received the minimally invasive total hip arthroplasty (MTHA), we monitor the pain level, functional capacity, and postural stability before and after operation within one year. In total of 23 subjects in our study, we found out that MTHA was effective in relieving pain in first 2 weeks and restoring the hip joint integrity, but the postural stability was influenced especially in tandem stand in both anterior-posterior and medial-lateral directions. The recovery of postural stability and functional capacity in one year duration fluctuated and no consistent improvement tendency was found. We suggested clinicians designing postsurgery rehabilitation program for consistent and progressive long-term recovery of postural stability and fall prevention to optimize surgical results and prevent undesired postoperative consequences.

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