Diurnal variations in the expression of core-clock genes correlate with resting muscle properties and predict fluctuations in exercise performance across the day

OBJECTIVES: In this study, we investigated daily fluctuations in molecular (gene expression) and physiological (biomechanical muscle properties) features in human peripheral cells and their correlation with exercise performance. METHODS: 21 healthy participants (13 men and 8 women) took part in three test series: for the molecular analysis, 15 participants provided hair, blood or saliva time-course sampling for the rhythmicity analysis of core-clock gene expression via RT-PCR. For the exercise tests, 16 participants conducted strength and endurance exercises at different times of the day (9h, 12h, 15h and 18h). Myotonometry was carried out using a digital palpation device (MyotonPRO), five muscles were measured in 11 participants. A computational analysis was performed to relate core-clock gene expression, resting muscle tone and exercise performance. RESULTS: Core-clock genes show daily fluctuations in expression in all biological samples tested for all participants. Exercise performance peaks in the late afternoon (15-18 hours for both men and women) and shows variations in performance, depending on the type of exercise (eg, strength vs endurance). Muscle tone varies across the day and higher muscle tone correlates with better performance. Molecular daily profiles correlate with daily variation in exercise performance. CONCLUSION: Training programmes can profit from these findings to increase efficiency and fine-tune timing of training sessions based on the individual molecular data. Our results can benefit both professional athletes, where a fraction of seconds may allow for a gold medal, and rehabilitation in clinical settings to increase therapy efficacy and reduce recovery times

Bed Rest, Exercise Countermeasure and Reconditioning Effects on the Human Resting Muscle Tone System

The human resting muscle tone (HRMT) system provides structural and functional support to skeletal muscle and associated myofascial structures (tendons, fascia) in normal life. Little information is available on changes to the HRMT in bed rest. A set of dynamic oscillation mechanosignals ([Hz], [N/m], log decrement, [ms]) collected and computed by a hand-held digital palpation device (MyotonPRO) were used to study changes in tone and in key biomechanical and viscoelastic properties in global and postural skeletal muscle tendons and fascia from a non-exercise control (CTR) and an exercise (JUMP) group performing reactive jumps on a customized sledge system during a 60 days head-down tilt bed rest (RSL Study 2015–2016). A set of baseline and differential natural oscillation signal patterns were identified as key determinants in resting muscle and myofascial structures from back, thigh, calf, patellar and Achilles tendon, and plantar fascia. The greatest changes were found in thigh and calf muscle and tendon, with little change in the shoulder muscles. Functional tests (one leg jumps, electromyography) showed only trends in relevant leg muscle groups. Increased anti-Collagen-I immunoreactivity found in CTR soleus biopsy cryosections was absent from JUMP. Results allow for a muscle health status definition after chronic disuse in bed rest without and with countermeasure, and following reconditioning. Findings improve our understanding of structural and functional responses of the HRMT to disuse and exercise, may help to guide treatment in various clinical settings (e.g., muscle tone disorders, neuro-rehabilitation), and promote monitoring of muscle health and training status in personalized sport and space medicine

Multipl skleroz hastalarında servikal mobilizasyonun tonus, pozisyon hissi ve denge üzerine etkisi

Çalışma, Multipl Skleroz hastalarında servikal mobilizasyonun tonus, pozisyon hissi ve denge üzerine etkisini araştırmak amacıyla yapıldı. Çalışmaya 14'ü kadın 2'si erkek olmak üzere toplam 16 birey dahil edildi. Çapraz geçişli dizayn edilen çalışmada bireyler rastgele yöntemle klasik rehabilitasyon ve servikal mobilizasyon tedavilerini farklı sırayla 4 hafta boyunca haftada 2 gün aldı. Tedaviler arasında bireyler 4 hafta arınma dönemi için bekletildi. Klasik rehabilitasyon için germe ve kuvvetlendirme, koordinasyon, denge ve yürüyüş egzersizlerinden oluşan bir program uygulanırken, servikal mobilizasyon için bu programa ek olarak servikal mobilizasyon eklem traksiyonu ve kaydırmalar ile yumuşak doku mobilizasyon tekniklerinden myofasyal gevşetme teknikleri uygulandı. Değerlendirmeler her iki tedavi programından önce ve sonra olmak üzere dört kere yapıldı. Bireylerin spastisitesi Modifiye Ashworth Skalası (MAS) ile; kasların viskoelastik özellikleri myotonPRO ile; eklem pozisyon hissi digital gonyometre ile; dengesi Berg Denge Ölçeği (BDÖ) ve Fonksiyonel Uzanma Testi (FUT)'yle; yürüme fonksiyonları Dinamik Yürüme İndeksi (DYİ) ve Zamanlı 25-Foot Yürüme Testi (T25W) ile değerlendirildi. Çalışmadan elde edilen sonuçlara bakıldığında, klasik tedaviyle birlikte verilen servikal mobilizasyonun spastisiteyi azalttığı ve hastaların dengesini iyileştirdiği gözlendi (p0,05). Sadece tonusun azaltılmasında sıra etkisi gözlenirken, öncelikle servikal mobilizasyonun yapılması ardından klasik fizyoterapinin uygulanmasının daha etkili olduğu gösterildi (p<0,05). Sonuç olarak tedavi etkinliği yönünden spastistenin azaltılması ve dengenin geliştirilmesi için servikal mobilizasyon uygulamalarının destekleyici olarak kullanılabileceği görüşüne varıldı. Servikal mobilizasyon uygulamalarının daha uzun tedavilerle pozisyon hissini geliştirebileceği düşünüldü. Ayrıca her iki uygulamanın spastisitede nöral ve non-nöral mekanizmayı etkileyerek birbirini tamamladığı görüldü. Farklı nörolojik hastalıklarda servikal bölge için manuel terapi protokolleri geliştirilerek uygulamaların etkinlikleri ve bu etkilerin ne kadar kalıcı olduğunu inceleyen çalışmalara ihtiyaç vardır. Anahtar Kelimeler: Kas tonusu, Manuel terapi, Multipl skleroz, Postural kontrol, Servikal Bölge

Feasibility of monitoring muscle health in microgravity environments using Myoton technology

Physical exercise is important for people living under extreme environmental conditions to stay healthy. Particularly in space, exercise can partially counteract the loss of muscle mass and muscle strength caused by microgravity. Monitoring the adaptation of the musculoskeletal system to assess muscle quality and devise individual training programmes is highly desirable but is restricted by practical, technical and time constraints on board the International Space Station. This study aimed to test the feasibility of using myometric measurements to monitor the mechanical properties of skeletal muscles and tendons in weightlessness during parabolic flights. The mechanical properties (frequency, decrement, stiffness relaxation time and creep) of the m. gastrocnemius, m. erector spinae and Achilles tendon were assessed using the hand-held MyotonPRO device in 11 healthy participants (aged 47 +/- A 9 years) in normal gravity as well as in microgravity during two parabolic flight campaigns. Results showed significant (p < .05-.001) changes in all mechanical properties of both muscles and the Achilles tendon, indicating a more relaxed tissue state in microgravity. Recordings from a phantom rubber material with the device in a test rig confirmed that the device itself was not affected by gravity, as changes between gravity conditions that were too small (< 1 %) to explain the changes observed in the tissues. It is concluded that myometric measurements are a feasible, easy-to-use and non-invasive approach to monitor muscle health in extreme conditions that prohibit many other methods. Real-time assessment of the quality of a muscle being exposed to the negative effect of microgravity and also the positive effects of muscular training could be achieved using Myoton technology

Investigating the impact of a spinal mobilisation intervention in people with multiple sclerosis

Background: Multiple Sclerosis (MS) has many disabling symptoms due to weakened signal propagation in the central nervous system. Manual therapeutics are often seen to have a positive effect on these symptoms with limited information as to why. The purpose of this project was to investigate a spinal mobilisation intervention, objectively measuring the changes it may be causing to muscle quality and movement patterns as a contribution to research in MS therapeutics. Methods: A series of 3 studies were designed to investigate the effects of a spinal mobilisation intervention on muscle quality and movement patterns. Study 1 tested people with lower back pain (LBP) as a pilot population (n=40), testing for an immediate effect on muscle quality. Study 2 replicated this with MS patients (n=20) assessing muscle quality, balance, and pain. Study 3 tested the intervention in a longer-term 4 bout study (n=20), assessing muscle quality, balance, pain, and fatigue. Results: Significant muscle stiffness reductions were seen in the LBP population post the intervention (p = 0.01, η2partial = 0.15). Baseline stiffness was found as a significant contributor (p = 0.002, R2 = 0.22). These muscular results were not replicated with the MS population. However, significant improvements in self-reported pain as a result of the intervention were revealed (p = 0.008, η 2partial = 0.33). Study 3 findings demonstrated significant improvements from baseline in balance and fatigue measures as a result of the intervention. High variability in the data are seen within the MS population. Conclusions: Four sessions were not sufficient to elicit a significant response in muscle quality as a result of the intervention in an MS population. However, significant improvements in balance and fatigue were revealed. Given the variability from the MS population, it is necessary to undertake a longer-term study and normalise baseline muscle quality values