Effect of localised vibration on muscle strength in healthy adults: a systematic review.

OBJECTIVE: To investigate the effects of local vibration on muscle strength in healthy adults. DATA SOURCES: The electronic databases PubMed, CINAHL, Scopus and Web of Science were searched using a combination of the following keywords: vibration, vibration therapy, power, maximal voluntary contraction, performance, rate of force development and vibratory exercise. In addition, the Medical Subject Headings 'vibration', 'strength' and 'exercise' were used. The bibliographical search was limited to articles published in English. STUDY SELECTION: Trials that evaluated the effect of localised vibration on muscle strength in healthy humans were included. DATA EXTRACTION: Two independent evaluators verified the quality of the selected studies using the PEDro Scale and the Cochrane Collaboration's tool for assessing the risk of bias. Muscle strength was calculated for each intervention. RESULTS: In total, 29 full-text studies were assessed for eligibility. Eighteen studies did not match the inclusion criteria, and were excluded. The 11 studies included in this review had an average PEDro score of 5.36/10. Most of the studies reported significant improvements in muscle strength after the application of local vibration. There was considerable variation in the vibration training parameters and target muscle location. CONCLUSIONS: The use of local vibration on the target muscle can enhance muscle strength in healthy adults. Further well-designed controlled studies are required to confirm the effect of local vibration training on muscle strength.

Effect of different head-neck-jaw postures on cervicocephalic kinesthetic sense.

OBJECTIVES: To investigate the effect of different induced head-neck-jaw postures on head-neck relocation error among healthy subjects. METHODS: 30 healthy adult male subjects participated in this study. Cervicocephalic kinesthetic sense was measured while standing, habitual sitting, habitual sitting with clenched jaw and habitual sitting with forward head posture during right rotation, left rotation, flexion and extension using kinesthetic sensibility test. RESULTS: Head-neck relocation error was least while standing, followed by habitual sitting, habitual sitting with forward head posture and habitual sitting with jaw clenched. However, there was no significant difference in error between different tested postures during all the movements. CONCLUSIONS: To the best of our knowledge, this is the first study to see the effect of different induced head-neck-jaw postures on head-neck position sense among healthy subjects. Assuming a posture for a short duration of time doesn't affect head-neck relocation error in normal healthy subjects.

Effect of quadriceps and hamstrings muscle cooling on standing balance in healthy young men.

OBJECTIVE: The present study compared the effect of quadriceps and hamstring muscle cooling on standing balance in healthy young men. METHODS: Thirty healthy young men (18-30 years) participated in the study. The participants were randomly assigned to three groups (n=10 each): quadriceps cooling (QC), hamstring cooling (HC), or control group (no cooling). Participants in the QC and HC groups received 20 minutes of cooling using a cold pack (gel pack), placed on the anterior thigh (from the apex of the patella to the mid-thigh) and the posterior thigh (from the base of the popliteal fossa to the mid-thigh), respectively. Balance score including unilateral stance was measured at baseline and immediately after the application of the cold pack. RESULTS: No significant difference in the balance score was noted in any group after the application of the cold pack (p⟩0.05). Similarly, no significant differences in post-test balance score were noted among the three groups (p⟩0.05). CONCLUSIONS: Cooling of the quadriceps and hamstring muscles has no immediate effect on standing balance in healthy young men. However, longitudinal studies are warranted to investigate the long-term effects of cooling these muscles on standing balance.

Efficacy of Rhus coriaria (sumac) juice in reducing muscle pain during aerobic exercise.

The main target of this study was to measure the influence of sumac juice drink on muscle indices and pain during an acute, intense exercise for 30 days. Forty healthy volunteers (15-25 years) were involved in aerobic exercise program for 4 weeks. Participants ingested sumac juice or placebo drink twice daily for 30 days. All participants were subjected for the evaluation of pain and estimation of serum: creatine kinase (CK), lactic acid dehydrogenase (LDH), troponin I, hydroxyproline (hyp), total antioxidant capacity (TAC), and in vitro antioxidant activity of sumac juice using pre-validated visual analog scale, colorimetric and immunoassays. The participants of both groups, placebo and sumac, showed an increment in pain scores both during exercise and post-exercise intervals. However, the sumac juice group showed a significant smaller increase in the pain scores compared to the placebo group. Participants in the sumac juice group were more willing to use the drink in the future. They achieved a higher satisfaction of sumac juice in ameliorating and the reduction of pain. Also, the sumac group showed a significant enhancement in the level of CK, LDH, troponin I, hyp, along with significant increase in serum (TAC) compared to the placebo group. The protective activity of muscle may relate to the antioxidant activity of phenolic component(s) in sumac juice as measured by 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging (87.9%) and ß-carotene-linoleic acid (68.7%) assays. These data suggest that oral administration of sumac juice may have a beneficial effect on muscle performance among athletes.