1. Institute of Sport Medicine, Faculty of Medicine, University of Maribor, 2000 Maribor, Slovenia</br>2. Institute for kinesiology research, Science and Research Centre Koper, 6000 Koper, Slovenia
Mr. Miloš Kalc
1. Institute of Sport Medicine, Faculty of Medicine, University of Maribor, 2000 Maribor, Slovenia</br>2. Institute for kinesiology research, Science and Research Centre Koper, 6000 Koper, Slovenia
Context: It has been recently demonstrated that tissue flossing around the ankle joint can be effectively used to improve ankle range of motion, jump, and sprint ability. However, there is a lack of studies investigating the acute effects of tissue flossing applied using different wrapping pressures. Objective: To investigate the acute effects of tissue flossing and the degree of floss band pressure, around the upper thigh on knee range of motion, strength, and muscle contractile characteristics. Design: Crossover design in 3 distinct sessions. Setting: University laboratory. Participants: A total of 19 recreationally trained volunteers (age 23.8[4.8] y) participated in this study. Intervention: Active knee extension and flexion performed for 3 sets of 2 minutes (2-min rest between sets with wrapped upper thigh). Individualized wrapping pressures were applied to create conditions of high and moderate vascular occlusion, while a loose band application served as a control condition. Main Outcome Measures: Participants were assessed for active straight leg raise test; tensiomyography displacement and contraction time for rectus femoris, vastus medialis, and biceps femoris muscles; and maximum voluntary contractions for knee extensors and flexors for pre, after, and 30 minutes after applying the floss band. Results: There was a statistically significant increase in maximum voluntary contractions for knee extensors and a significant shortening in rectus femoris contraction time for the moderate condition, which was associated with small to medium effects in favor of the moderate condition. There were no statistically significant changes observed between control and high conditions. The active straight leg raise test was unaffected regardless of intervention. Conclusions: The results of this study suggest that tissue flossing around the upper thigh might have a localized as well as pressure-sensitive response, thereby improving neuromuscular function of the knee extensors.
Context: Recently, a few papers have suggested that tissue flossing (TF) acutely improves range of motion (ROM) and neuromuscular performance. However, the effects of TF on muscle contractile properties are yet to be defined. Objective: To investigate the acute effects of TF on ankle ROM and associated muscle gastrocnemius medialis displacement and contraction time assessed with tensiomyography. Design: Crossover design in a single session. Setting: University laboratory. Participants: Thirty recreationally trained volunteers (age 23.00 [4.51] y). Intervention: Active ankle plantar flexion and dorsiflexion were performed for the duration of 2 minutes (3 sets, 2-min rest between sets), while a randomly selected ankle was wrapped using TF elastic band (BAND) and the other ankle served as a control condition (CON). Main Outcome Measures: Participants performed an active ankle plantar flexion and dorsiflexion ROM test and muscle gastrocnemius medialis tensiomyography displacement and contraction time measurement pre, 5, 15, 30, and 45 minutes after the floss band application. Results: There were no statistically significant differences between BAND and CON conditions (active ankle plantar flexion ROM: P = .09; active ankle dorsiflexion ROM: P = .85); however, all ROM measurements were associated with medium or large effect sizes in favor of BAND compared with CON. No significant changes were observed in the tensiomyography parameters. Conclusions: The results of this study suggest that TF applied to the ankle is a valid method to increase ROM and at the same time maintaining muscular stiffness.
1 December 2012 in Journal of Exercise Science & Fitness
The diagnostic accuracy of tensiomyography (TMG) parameters compared to the gold standard in neuromuscular fatigue evaluation using voluntary and electrically induced muscle activation is unclear. This study aimed to investigate the diagnostic accuracy of TMG parameters to detect individual changes after interventions that were designed to induce central or peripheral fatigue. Nineteen males (age: 32.2 ± 9.3 years) performed two interventions, consisting of maintaining 25% of maximal voluntary contraction (MViC25%) and a 30 s all-out cycling test (Wingate), respectively. TMG parameters, maximum voluntary contraction (PtMViC), voluntary activation (VA%) and electrically elicited double twitches (Dtw) were assessed on the knee extensors before (PRE), one minute (POST) and seven minutes after (POST7) the intervention. The diagnostic accuracy (AUC) of TMG parameters were evaluated in comparison to two criteria measures (PtMViC and Dtw). RM ANOVA revealed a significant interaction between the effects of intervention and time on VA% (p = 0.001) and Dtw (p < 0.001) but not for PtMViC (p = 0.420). AUC showed that TMG parameters had a good ability in detecting muscular fatigue assessed by Dtw but not by PtMViC. The results of the current study suggest that TMG parameters can be used to monitor peripheral neuromuscular fatigue.
The purpose of this study was to investigate the effects of tissue flossing applied to the ankle joint or to the calf muscles, on ankle joint flexibility, plantarflexor strength and soleus H reflex. Eleven young (16.6 ± 1.2 years) martial arts fighters were exposed to three different intervention protocols in distinct sessions. The interventions consisted of wrapping the ankle (ANKLE) or calf (CALF) with an elastic band for 3 sets of 2 min (2 min rest) to create vascular occlusion. A third intervention without wrapping the elastic band served as a control condition (CON). Active range of motion for ankle (AROM), plantarflexor maximum voluntary contraction (MVC), and soleus H reflex were assessed before (PRE), after (POST), and 10 min after (POST10) the intervention. The H reflex, level of pain (NRS) and wrapping pressure were also assessed during the intervention. Both CALF and ANKLE protocols induced a significant drop in H reflex during the intervention. However, the CALF protocol resulted in a significantly larger H reflex reduction during and after the flossing intervention (medium to large effect size). H reflexes returned to baseline levels 10 min after the intervention in all conditions. AROM and MVC were unaffected by any intervention. The results of this study suggest that tissue flossing can decrease the muscle soleus H reflex particularly when elastic band is wrapped around the calf muscles. However, the observed changes at the spinal level did not translate into higher ankle joint flexibility or plantarflexor strength.
Leveraging both intramuscular and high-density surface EMG recordings in the vastus lateralis, we identified alterations in motor unit (MU) properties in young adults after 21 days of bed rest. These included reduced discharge rates and changes in MU potential size and complexity, observed at both low and moderate contraction intensities. Evidence of impaired neuromuscular junction (NMJ) function and denervation was also found. Our findings indicate that medium-term disuse elicits MU-level changes not detected in shorter-duration studies.