Consideration for Lumbar Disc Degeneration and Herniation in Sports

Lower-back related injuries in an athletic population are common and may have severe implications for the athletes sporting career. The focus of this work was to review epidemiology, intervention strategies, and recommendations for return to practice and competition for athletes with lumbar disc degeneration and herniated disc. Conservative treatments for discogenic degeneration and lumbar spine herniation are generally sufficient for athletic populations to restore functional movement. Athletes that fail to respond to conservative measures may consider lumbar discectomy, with high levels of return to pre-competition levels observed following effective surgery. Surgical procedures such as spinal fusion and disc replacement require careful consideration, and should only be recommended if the athlete fails to respond to vigorous conservative treatments. Spinal disc implants have durability and mechanical loading concerns, whereas spinal fusion may ultimately prevent participation in contact sports. Specific guidelines for return to practice and competition remain poorly defined, thus future investigations should address this gap in knowledge. Return to sports should be carefully recommended after the athlete demonstrates sufficient improvements in neuro-physiological, biomechanical, and psychological domains. The correct rehabilitative exercise programme is vital to the rehabilitation of athletes following injury, and should consider frequent monitoring of pain, range of motion and muscle function

Interlimb Asymmetries and Ipsilateral Associations of Plantar Flexors and Knee Extensors Rate-of-Force Development Scaling Factor

Rate of force/torque development scaling factor (RFD-SF/RTD-SF) was recently introduced as a tool to quantify the neuromuscular quickness, and it could have potential for interlimb asymmetry identification. Moreover, positive relationships in RFD-SF ability among different muscle groups were shown, but not in the lower extremity. The first aim of our study was to use RTD-SF for interlimb asymmetry identification. The second aim was to determine associations between plantar flexors (PF) and knee extensors (KE). Forty young healthy athletes (14.8 +/- 1.2 years) performed explosive isometric contractions to a span of torque levels for PF and KE. From rapid isometric contractions, the RTD-SF and linearity (r(2)) of the regression line were calculated. Using RTD-SF we identified 10% (PF) and 15% (KE) of subjects with contralateral asymmetries ( gt 15% criterion). The results revealed significant positive moderate correlation in RTD-SF between PF and KE (r = 0.401, p lt 0.05). We supported that RTD-SF can be a useful tool for interlimb asymmetry identification. Future research about observed asymmetry in rapid submaximal contractions deserves more attention, as most of the functional sport specific activities put high demands on rapid force production. Our study as first confirmed positive associations in RTD-SF ability between muscle groups in lower limbs

Proposal for progressive loading of the hip abductors under mechanically unstable conditions: An electromyography study

The aim of this study was to test the effect of the stance width and asymmetry on muscle activation patterns during balancing on a tilt board. Eleven young healthy volunteers took part in the tests. After the standardized warm-up and customization protocol had been carried out, they balanced five times for 60 seconds on a tilt board, using a different foot position each time - (i) wide symmetrical, (ii) narrow symmetrical, (iii) moderate asymmetrical, (iv) extreme asymmetrical, and (v) single leg. Pair of electromyographic electrodes was glued over the gluteus medius muscle on both sides from which signals were acquired. The average values of the pre-processed signals were normalized and quantified. Repeated measures analysis of variance and t-tests revealed a systematic effect of the foot positions on the amount of the gluteus medius activation. Its activation was significantly increased in both asymmetrical stances when the foot was moved closer to the tilt board`s axis of rotation and most prominently when the single leg stance was used. These results point out the importance of the foot positioning for the actual muscle function while balancing on a tilt board. We believe that different levels of feet positioning asymmetry should be used for gradual loading of the extremity and for provoking activity in hip side stabilizers

Strength, jumping and change of direction speed asymmetries in soccer, basketball and tennis players

Despite growing research in the field of inter-limb asymmetries (ILAs), little is known about the variation of ILAs in different populations of athletes. The purpose of this study was to compare ILAs among young basketball, soccer and tennis players. ILAs were assessed in three different types of tests (strength, jumping and change of direction (CoD) speed), each including different tasks: (1) bilateral and unilateral counter movement jump, (2) isometric strength of knee extensors (KE) and knee flexors (KF), and (3) 90° and 180° CoD. Generally, the absolute metrics showed strong reliability and revealed significant differences (p < 0.05) among the three groups in KE maximal torque, KE and KF rate of force development and in both CoD tests. For jumping ILAs, power and force impulse metrics exhibited significant between-limb differences between groups, compared to jump height. For strength and CoD speed ILAs, only KF maximal torque and 180° CoD exhibited significant differences between groups. Greater KF strength ILAs in soccer players and counter-movement jump ILAs in tennis players are most probably the result of sport-specific movement patterns and training routines. Sport practitioners should be aware of the differences in ILAs among sports and address training programs accordingly

Long-term high-level exercise promotes muscle reinnervation with age.

The histologic features of aging muscle suggest that denervation contributes to atrophy, that immobility accelerates the process, and that routine exercise may protect against loss of motor units and muscle tissue. Here, we compared muscle biopsies from sedentary and physically active seniors and found that seniors with a long history of high-level recreational activity up to the time of muscle biopsy had 1) lower loss of muscle strength versus young men (32% loss in physically active vs 51% loss in sedentary seniors); 2) fewer small angulated (denervated) myofibers; 3) a higher percentage of fiber-type groups (reinnervated muscle fibers) that were almost exclusive of the slow type; and 4) sparse normal-size muscle fibers coexpressing fast and slow myosin heavy chains, which is not compatible with exercise-driven muscle-type transformation. The biopsies from the old physically active seniors varied from sparse fiber-type groupings to almost fully transformed muscle, suggesting that coexpressing fibers appear to fill gaps. Altogether, the data show that long-term physical activity promotes reinnervation of muscle fibers and suggest that decades of high-level exercise allow the body to adapt to age-related denervation by saving otherwise lost muscle fibers through selective recruitment to slow motor units. These effects on size and structure of myofibers may delay functional decline in late aging

FES Training in Aging: interim results show statistically significant improvements in mobility and muscle fiber size

Aging is a multifactorial process that is characterized by decline in muscle mass and performance. Several factors, including reduced exercise, poor nutrition and modified hormonal metabolism, are responsible for changes in the rates of protein synthesis and degradation that drive skeletal muscle mass reduction with a consequent decline of force generation and mobility functional performances. Seniors with normal life style were enrolled: two groups in Vienna (n=32) and two groups in Bratislava: (n=19). All subjects were healthy and declared not to have any specific physical/disease problems. The two Vienna groups of seniors exercised for 10 weeks with two different types of training (leg press at the hospital or home-based functional electrical stimulation, h-b FES). Demografic data (age, height and weight) were recorded before and after the training period and before and after the training period the patients were submitted to mobility functional analyses and muscle biopsies. The mobility functional analyses were: 1. gait speed (10m test fastest speed, in m/s); 2. time which the subject needed to rise from a chair for five times (5x Chair-Rise, in s); 3. Timed &ndash;Up-Go- Test, in s; 4. Stair-Test, in s; 5. isometric measurement of quadriceps force (Torque/kg, in Nm/kg); and 6. Dynamic Balance in mm. Preliminary analyses of muscle biopsies from quadriceps in some of the Vienna and Bratislava patients present morphometric results consistent with their functional behaviors. The statistically significant improvements in functional testings here reported demonstrates the effectiveness of h-b FES, and strongly support h-b FES, as a safe home-based method to improve contractility and performances of ageing muscles

Effects of Munari powder on physical and sensory-motor parameters: a preliminary report

Munari powder is broadly used in physical medicine and rehabilitation to decrease pain and help normalize sensory-motor function. It operates as TPRV1 agonist and “stops” generation of action potentials in pain nerve fibers. This is a short report of a pilot study on 20 subjects. Every subject underwent four visits to our laboratory, where the Munari applications and related measurements of its effects took place. Each of the healthy adults received the following applications: (1) placebo, i.e. 0% cayenne pepper mixture, consisting only of water and kaolin, (2) weak, i.e. 2.5% cayenne pepper mixture, (3) medium, i.e. 5.0% cayenne pepper mixture, and (4) strong, i.e. 10% cayenne pepper mixture. The assessments were carried out before the Munari powder patch application, right after the application, and 15 and 30 min after the termination of the 20-minute Munari powder patch application. We measured subjective cold/hot feeling on visual analogue scale, blood pressure, body temperature, skin light touch sensations, sense for two-point discrimination, and pain threshold to the mechanical stimulus. Besides these tests, maximal voluntary force during isometric trunk extension and the sitting balance test were performed. The preliminary results indicate that the 5% concentration of cayenne pepper mixture is the best choice because no additional effects were observed with the 10% concentration and the effects are higher than with 2.5% concentration. Whether this will be also thrue for the patients suffering pain ought to be determined