Cervical muscle strength measurement in two groups of elite Greco-Roman and free style wrestlers and a group of non-athletic subjects

Cervical spine characteristics differ in competitive combat athletes compared with active control participants

BACKGROUND

Injury to the head and neck are common in combat sport athletes. Impairments of the cervical spine have been found in some athletes who participate in sports with high forces and collisions. There is a lack of research on the effects of combat sports on the cervical spine.

OBJECTIVE

The primary study aim was to investigate differences in cervical spine characteristics between combat athletes and a similarly aged active control group. The secondary aim was to investigate the relationship between symptom-based outcome measures and characteristics of the cervical spine.

DESIGN

Cross-sectional.

METHOD

40 male adult combat sport athletes and 40 male adult control participants were recruited from 4 combat sport clubs and a university campus, Australia. Cervical spine assessments were conducted at a private physiotherapy clinic. The Neck Disability Index and the Post-Concussion Symptom Scale were used as symptom-based outcome measures.

RESULTS

Combat sport athletes had a reduced range of cervical motion, but greater isometric strength and endurance compared with a control group (p < 0.05). The Neck Disability Index and Post-Concussion Symptom Scale were negatively correlated with cervical spine range of motion and isometric strength, meaning that higher scores correlated with a reduction in function.

CONCLUSIONS

Differences were observed in characteristics of the cervical spine in combat sport athletes compared with a control group. Higher symptom-based outcome scores correlated with reduced range of motion and strength of cervical spine muscles. Further investigation to establish clinical cut-off scores for functional impairment may be warranted.

Neck strength in Rugby Union players: a systematic review of the literature

The incidence and severity of concussion injuries are increasing every year. Scientific evidence indicates that neck strength and girth could play a role in preventing head and neck injuries, or at least mitigating their severity. We aimed to examine the scientific literature addressing neck strength in Rugby Union with a focus on the potential role of neck strength on injury incidence, neck assessment protocols, neck strength measures, and neck strengthening exercises.We conducted a systematic search of the literature in January 2021 to locate published peer-reviewed articles from PubMed, SPORTDiscus^TM, Web of Science®, and Scopus® e-databases. Overall, senior elite male players were stronger than younger-aged players. Forwards were stronger in extension than any other directions assessed, and were generally stronger and possessed larger necks and greater cross-sectional areas when compared to backs. Implementation of isometric exercise routines in professional players was reported to improve neck strength in all directions. There were no studies evaluating the incidence of concussion and neck strength or neck strengthening strategies in Rugby Union. Strengthening the neck continues to be one of the targeted modifiable risk factors with respect to limiting the severity and temporal effects of head injuries in Rugby Union, despite limited evidence regarding direct associations between neck strength and concussion.

Identification of success factors in elite wrestlers-An exploratory study

Identification of success factors in wrestling as well as establishing their hierarchy are crucial from a cognitive and practical standpoint. It may provide a lot of practical recommendations related to wrestling-specific training. The aim of this study was to identify and establish the hierarchy of success factors in wrestling regardless of a fighting style and weight class. This study included 168 elite male freestyle and Greco-Roman wrestlers. They were divided into two groups: athletes who won medals (successful wrestlers) in high-rank competitions (Polish Championships or higher) and those who did not win any medals (less successful wrestlers) in those competitions. The following elements were assessed: anthropological measurements, body composition, dynamic strength, strength endurance, agility, special endurance, wrestling-specific fitness, response time, technical wrestling skills and anaerobic capacity. For initial data analysis, one-way ANOVA (α = 0.005) was used. Random Forests classifier was employed to identify success factors and to determine the importance of each of these factors in terms of sports performance. Seven key success factors were identified: anaerobic power, strength endurance, response time, special endurance, wrestling-specific fitness and technical wrestling skills performed in a horizontal position. Random Forests turned out to be an effective method of modelling success in wrestling (compared to SVM and KNN, which were also used in the study). These findings suggest that wrestling-specific training can be effectively monitored by controlling several vital indicators of athletes’ preparedness: anaerobic power, strength endurance, response time, special endurance, wrestling-specific fitness and technical wrestling skills (the performance of reverse waistlock from a standing position and trunk grip gut wrench assessed by experts).

Physical Fitness and Anthropometric Measures of Young Brazilian Judo and Wrestling Athletes and Its Relations to Cardiorespiratory Fitness

This study aimed to compare the anthropometric profile and physical fitness of young judo and wrestling athletes. Twenty-four young athletes (judo (n = 13) and wrestling (n = 11)) participated in this study. The first visit involved anthropometric and flexibility evaluation, abdominal endurance test, upper limbs resistance and cardiorespiratory test. After 48 h, horizontal jump test (HJT), vertical jump test (VJT), medicine ball throw test (MBT), chin-up test (CUT), chin-up isometric test (CUIT) and the anaerobic resistance test were performed. Judo athletes presented greater values for body mass (p = 0.020), height (p = 0.010), and body mass index (p = 0.026) than wrestlers. Judo athletes also performed better for abdominal endurance (p = 0.044), upper limb resistance tests (p < 0.001), VJT (p = 0.022) and MBT (p = 0.023) than wrestling athletes. These results suggest that young judo athletes presented a higher performance in abdominal endurance, upper limbs resistance, HJT, VJT and MBT than wrestling athletes, suggesting that strength and conditioning are related to modality specificity.

Effects of different dosages of caffeine administration on wrestling performance during a simulated tournament

The aim of the present study was to investigate the effects of different forms of caffeine administration on physical performance during a simulated wrestling tournament. In a double-blind and randomized experiment, twelve male freestyle wrestlers competed in a simulated wrestling tournament (5 wrestling matches consisting of 2 × 3-min wrestling rounds) following the ingestion of: a placebo, a high-dose of caffeine (10 mg/kg), a moderate-dose caffeine (4 mg/kg), a repeated-dose caffeine (2 mg/kg before each match to a total of 10 mg/kg) or a selective caffeine administration based on performance decrement previously measured (6.16 ± 1.58 mg/kg). The Pittsburgh Wrestling Performance Test (PWPT) was measured before each match to assess physical performance. In comparison to the placebo, the high dose of caffeine only reduced PWPT time before the first match (56.8 ± 2.0 vs. 52.9 ± 1.8 s; p < .05). The moderate dose of caffeine did not affect PWPT performance during the tournament. Both, the repeated dose and the selective administration of caffeine reduced PWPT time with respect to the placebo in the third (66.7 ± 1.8 vs. 63.1 ± 1.4 s; p < .05) and fourth matches (72.3 ± 2.4 vs. 65.9 ± 1.3 s; p < .05). However, only the selective dose of caffeine reduced PWPT time before the fifth match (62.7 ± 3.0 vs. 56.3 ± 2.0; p < .05). The dosage and administration of caffeine affect the ergogenic effects obtained following the ingestion of this substance. An individualized protocol to provide caffeine when physical performance is expected to be reduced might improve wrestling performance during the latter stages of a tournament.

Physical and Physiological Attributes of Wrestlers: An Update

Chaabene, H, Negra, Y, Bouguezzi, R, Mkaouer, B, Franchini, E, Julio, U, and Hachana, Y. Physical and physiological profile of wrestler athletes: a short review. J Strength Cond Res 31(5): 1411-1442, 2017-Wrestling is one of the oldest combat sports, disputed since the ancient Greek Olympic Games. This combat sport discipline has caught the attention of scientists since 1943 which is the date that matches the appearance of the first scientific research dealing with wrestling. The current short review aimed to summarize and critically analyze the scientific literature related to wrestling's physical and physiological attributes and to provide practical recommendations for testing/training together with new perspective and areas of future scientific research. Regardless of sex and wrestling styles, an optimal level of cardiorespiratory fitness is important to help sustaining effort throughout the duration of the match and to stimulate the recovery process between periods. With regard to the anaerobic power and capacity, the available studies were in agreement about their critical importance toward reaching high-level wrestling success since these variables have discriminated well between successful and less-successful wrestlers regardless of age, weight classes, and wrestling styles. Physical fitness parameters such as maximal dynamic strength, isometric strength, explosive strength, and strength endurance are closely related to high-level wrestling performance. However, flexibility level seems not to be one of the key fitness variables that help to reach high-level wrestling success. Overall, to achieve high-level wrestling performance, training should be directed to develop anaerobic power and capacity, aerobic power, maximal dynamic and isometric strength, explosive strength, and strength endurance.

The envelope of motion of the cervical spine and its influence on the maximum torque generating capability of the neck muscles

The posture of the head and neck is critical for predicting and assessing the risk of injury during high accelerations, such as those arising during motor accidents or in collision sports. Current knowledge suggests that the head's range-of-motion (ROM) and the torque-generating capability of neck muscles are both dependent and affected by head posture. A deeper understanding of the relationship between head posture, ROM and maximum torque-generating capability of neck muscles may help assess the risk of injury and develop means to reduce such risks. The aim of this study was to use a previously-validated device, known as Neck Flexibility Tester, to quantify the effects of head's posture on the available ROM and torque-generating capability of neck muscles. Ten young asymptomatic volunteers were enrolled in the study. The tri-axial orientation of the subjects' head was controlled via the Neck Flexibility Tester device. The head ROM was measured for each flexed, extended, axially rotated, and laterally bent head's orientation and compared to that in unconstrained neutral posture. Similarly, the torque applied about the three anatomical axes during Isometric Maximum Voluntary Contraction (IMVC) of the neck muscles was measured in six head's postures and compared to that in fully-constrained neutral posture. The further from neutral the neck posture was the larger the decrease in ROM and IMVC. Head extension and combined two-plane rotations postures, such as extension with lateral bending, produced the largest decreases in ROM and IMVC, thus suggesting that these postures pose the highest potential risk for injury.

Influence of Cervical Muscle Fatigue on Musculo-Tendinous Stiffness of the Head-Neck Segment during Cervical Flexion

AIM

The aim of this study is to determine if the fatigue of cervical muscles has a significant influence on the head-neck segment musculo-tendinous stiffness.

METHODS

Ten men (aged 21.2 ± 1.9 years) performed four quick-release trials of flexion at 30 and 50% MVC before and after the induction of muscular fatigue on cervical flexors. Electromyographic activity was recorded on the sternocleidomastoids (SCM) and spinal erectors (SE), bilaterally. Musculo-tendinous stiffness was calculated through the quick-release method adapted to the head-neck segment.

RESULTS

We noticed a significant linear increase of the head-neck segment musculo-tendinous stiffness with the increase of exertion level both before (P < 0.0001) and after the fatigue procedure (P < 0.0001). However, this linear relationship was not different before and after the fatigue procedure. EMG analysis revealed a significant increase of the root mean square for the right SCM (P = 0.0002), the left SCM (P < 0.0001), the right SE (P < 0.0001), and the left SE (P < 0.0001) and a significant decrease of the median power frequency only for the right (P = 0.0006) and the left (P = 0.0003) SCM with muscular fatigue.

DISCUSSION

We did not find significant changes in the head-neck segment musculo-tendinous stiffness with fatigue of cervical muscles. We found a significant increase in EMG activity in the SCM and the SE after the induction of fatigue of the SCM. Our findings suggest that with fatigue of cervical flexors, neck muscle activity is modulated in order to maintain the musculo-tendinous stiffness at a steady state.

Paraspinal muscle morphometry in cervical spondylotic myelopathy and its implications in clinicoradiological outcomes following central corpectomy

Object

The objective of this study was to assess the cross-sectional areas (CSAs) of the superficial, deep flexor (DF), and deep extensor (DE) paraspinal muscles in patients with cervical spondylotic myelopathy (CSM), and to evaluate their correlations with functional status and sagittal spinal alignment changes following central corpectomy with fusion and plating.

Methods

In this retrospective study of 67 patients who underwent central corpectomy with fusion and plating for CSM, the CSAs of the paraspinal muscles were calculated on the preoperative T2-weighted axial MR images and computed as ratios with respect to the corresponding vertebral body areas (VBAs) and as flexor/extensor CSA ratios. These ratios were then compared with those in the normative population and analyzed with respect to various clinicoradiological factors, including pain status, Nurick grade, and segmental angle change at follow-up (SACF).

Results

The mean CSA values for all muscle groups and the DF/DE ratio were significantly lower in the study cohort compared with an age- and sex-matched normative study group (p < 0.001). Among various independent variables tested in a multivariate regression analysis, increasing age and female sex significantly predicted a lower total extensor CSA/VBA ratio (p < 0.001), while a longer duration of symptoms significantly predicted a greater total flexor/total extensor CSA ratio (p = 0.02). In patients undergoing single-level corpectomy, graft subsidence had a positive correlation with SACF in all patients (p < 0.05), irrespective of the preoperative segmental angle and curvature, while in patients undergoing 2-level corpectomy, graft subsidence demonstrated such a correlation only in the subgroup with lordotic curvatures (p = 0.02). Among the muscle area ratios, the DF/DE ratio demonstrated a negative correlation with SACF in the subgroup with preoperative straight or kyphotic segmental angles (p = 0.04 in the single corpectomy group, p = 0.01 in the 2-level corpectomy group). There was no correlation of any of the muscle ratios with change in Nurick grade.

Conclusions

Patients with CSM demonstrate significant atrophy in all the flexor and extensor paraspinal muscles, and also suffer a reduction in the protective effect of a strong DF/DE CSA ratio. Worsening of this ratio significantly correlates with greater segmental kyphotic change in some patients. A physiological mechanism based on DF dysfunction is discussed to elucidate these findings that have implications in preventive physiotherapy and rehabilitation of patients with CSM. Considering that the influence of a muscle ratio was significant only in patients with hypolordosis, a subgroup that is known to have facetal ligament laxity, it may also be postulated that ligamentous support supersedes the influence of paraspinal muscles on postoperative sagittal alignment in CSM.

Muscle strength quantification in small animals: a new transcutaneous technique in rabbits

The objective of this study was to develop a new, simple, and noninvasive technique to measure the force produced by dorsi-flexion of the foot in small animals. In addition, this study aimed to quantitatively describe changes in muscle and soft tissue structures using histomorphometry. The recovery of the dorsi-flexing muscles in the tibialis anterior compartment in New Zealand White rabbits was evaluated after musculoskeletal trauma by measuring isometric contractions after submaximal transcutaneous electrical stimulation of the peroneal nerve. The trauma included muscle and bone trauma that was treated with limb shortening followed by distraction osteogenesis. Muscle contractions were initiated at an amplitude of 5.1 mA for a duration of 2.56 ms at intervals of 50 ms. Based on consecutive measurements of the force on days 5, 10, 15, 20, 25, and 30 postsurgery, a positive trend in recovery of the stimulated force produced by dorsi-flexion of the foot was observed. The muscle strength at 30 days postsurgery was compared to that measured presurgery (baseline): 55% of the animals had dorsi-flexion strength that was 60% below that of the presurgery baseline muscle strength; 36% of the animals had dorsi-flexion strength that was greater than 60% of the baseline measure, indicating that there was a significant decrease in force produced by dorsi-flexion of the foot after trauma on all testing days (p < 0.01) and that a severe muscular injury was set with limited recovery. This technique provides a new option for examining muscle regeneration and rehabilitation in small animals.

Sport-specific characteristics of trunk muscles in collegiate wrestlers and judokas

This study evaluated the sport-specific characteristics of the cross-sectional areas (CSAs) of trunk muscles and trunk muscle strength in wrestlers and judokas. We also examined whether their trunk muscles and muscle strength depended on athletic performance levels in each sport. The subjects comprised 14 male collegiate wrestlers and 14 judokas. Magnetic resonance imaging was used to assess the trunk muscle CSAs at the L3-4 level parallel to the lumbar disc space. A Biodex System3 was used to measure isokinetic trunk flexor and extensor muscle strength of peak torque, work, average torque, and average power. The absolute and relative CSAs of the trunk muscles in the wrestlers and judokas were significantly different (rectus abdominis: wrestling > judo, P < 0.05; obliques: wrestling < judo, P < 0.05; quadratus lumborum: wrestling < judo, P < 0.01). We confirmed that the absolute and relative trunk extensor and flexor strength of peak torque, work, and average torque were significantly higher in the collegiate wrestlers than in judokas. On athletic performance, the tendency of the CSAs and muscular strength of trunk muscles was not consistent with athletic performance levels in each sport. Our findings indicated that the sport-specific characteristics of the CSAs of the trunk muscles and trunk muscle strength obviously differed between the 2 similar sports. Athletes should practice the sport-specific training of trunk muscles and develop sport specificity in their sports. Particularly, wrestlers have to train in trunk flexion and extension motions, and judokas need to strengthen trunk rotation and lateral flexion motions. This information will be available for athletes as well as strength and technical training coaches in wrestling, judo, and the other sports.

The importance of isometric maximum strength in college wrestlers

Previous research has demonstrated the importance of isometric maximal strength (PF) and rate of force development (RFD) in a variety of athletic populations including track cyclists and track and field athletes. Among coaches and sports scientists there is a lack of agreement regarding how much strength is required for optimal performance in most sports. The purpose of this study was to examine relationships between measures of PF, RFD and one repetition maximum (1RM) strength with other variables that might contribute to successful performance in collegiate wrestlers. Eight men (M = 20.0, SD = 0.4 years; Height M = 1.68, SD = 0. 13 m; Mass M = 78.0, SD = 4.2 kg) who were Division III college wrestlers participated in this study. They were tested for PF using the isometric mid thigh pull exercise. Explosive strength was measured as RFD from the isometric force-time curve. The 1RM for the squat, bench press and power clean exercises were determined as a measure of dynamic strength. Vertical jump height was measured to determine explosive muscular power. The wrestlers also ranked themselves and the coaches of the team also provided a ranking of the athletes. Correlations between the variables were calculated using the Pearson product moment method. Results indicated strong correlations between measures of PF and 1RM (r = 0.73 - 0.97). The correlations were very strong between the power clean 1RM and PF (r = 0.97) and squat 1RM and PF (r = 0.96). There were no other significant correlations with other variables apart from a strong correlation between RFD and coaches ranking (r = 0.62). Findings suggest that isometric mid thigh pull test does correlate well with 1RM testing in college wrestlers. RFD does not appear to be as important in college wrestlers. The isometric mid thigh pull provides a quick and efficient method for assessing isometric strength in athletes. This measure also provides a strong indication of dynamic performance in this population. The lack of strong correlations with other performance variables may be a result of the unique metabolic demands of wrestling. Key PointsIn Division III collegiate wrestlers the isometric mid thigh pull test correlates well with 1RM testing.Rate of Force Development does not appear to be as important in college wrestlers.The lack of strong correlations with other performance variables may be a result of the unique metabolic demands of wrestling.