A non-randomised experimental feasibility study into the immediate effect of three different spinal manipulative protocols on kicking speed performance in soccer players

Characteristics of the Kicking Motion in Adolescent Male Soccer Players Who Develop Osgood-Schlatter Disease: A Prospective Study

Background:

Osgood-Schlatter disease (OSD) is an apophysitis of the tibial tubercle caused by repeated traction of the patellar tendon during adolescence. Although OSD is associated more with sports such as soccer, it remains unclear whether the kicking motion itself is related to OSD onset.

Purpose:

To prospectively evaluate the kicking motion in adolescent soccer players who later developed OSD.

Study Design:

Case-control study.

Methods:

The authors observed 47 Japanese adolescent male soccer players (mean age, 12 years) over 6 months in 2018-2019; none of the participants had OSD at study onset. The players underwent tibial tubercle ultrasound at baseline, and their kicking motion was evaluated using 3-dimensional (3D) motion analysis with 65 reflective markers. The 3D angle of the lumbar spine, thorax, and pelvis and the angular velocity of the hips, knees, and ankles were calculated for the support leg. The kicking motion was divided into 8 phases, and ball speed, kicking time, and positions of the support (nonkicking) leg and center of mass (COM) from the ball were calculated for each phase. Six months later, the players underwent another ultrasound and were divided into 2 groups: those diagnosed with OSD in the support leg (OSD group) and those without OSD (normal [NRL] group). All factors calculated using the kicking motion analysis at the baseline were compared between groups.

Results:

There were 19 players in the OSD group and 28 players in the NRL group. Anthropometric measurements, ball speed, and kicking time were similar between the 2 groups. The forward translation of the COM and the support leg, the flexion angle of the thorax, and the rotation angle of the pelvis before impact with the ball were all significantly smaller in the OSD group than in the NRL group (P < .05). Moreover, the knee extension angular velocity of the support leg was significantly larger in the OSD group (P < .05) at ball impact.

Conclusion:

A kicking motion with small COM translation, small thoracic flexion, and small pelvic rotation before ball impact, as well as large knee extension angular velocity of the support leg at ball impact, may be associated with OSD onset.

A process evaluation of the Mind Your Back trial examining psychologically informed physical treatments for chronic low back pain

Background

In chronic conditions, such as back pain, the use of interventions that address physical, social and psychological aspects within a biopsychosocial framework are encouraged, however, applying this holistic multimodal approach in physical therapy practice (i.e., chiropractic and physiotherapy) is challenging. To explore the problem of delivering a biopsychosocially informed package of care in physical therapy practice a recent randomised control trial (RCT) called ‘Mind Your Back’ was conducted to evaluate the effectiveness of a combined physical and internet-delivered psychological intervention (psychologically informed physical treatments) compared to standard treatment for improving disability and self-efficacy in people with chronic LBP. The results of the trial indicated no difference between the two intervention groups. Although high-quality RCTs are considered gold standard for effectiveness of interventions, qualitative research methods embedded within a process evaluation framework are also used to reveal other issues and important information that help to explain clinical trial results, and to further the field of digital health interventions research. Therefore, within a process evaluation framework, the aim is to explore participants experiences of the interventions received throughout the Mind Your Back trial which led to a null result.

Methods

In-line with recommendations for a process evaluation this study used in-depth interviews and qualitative thematic analysis with participants of both arms of the trial 5–6 months after study completion. Semi-structured telephone interviews were conducted with twenty-five participants to explore their experiences of taking part in the Mind Your Back trial. Interviews were conducted in November 2017, transcribed verbatim and data analysed thematically.

Results

Two main themes were identified: (1) Personalised support and therapeutic alliance are important, and (2) MoodGYM lacked relevant, personalised and tailored support.

Conclusion

It is important to deliver tailored digital health supports that is personalised and fosters a therapeutic alliance.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12998-021-00389-y.

Acute Effects of Warm-Up, Exercise and Recovery-Related Strategies on Assessments of Soccer Kicking Performance: A Critical and Systematic Review

BACKGROUND

A number of reviews have collated information on the impact of warming-up, physical exertion and recovery strategies on physical, subjective and physiological markers in soccer players yet none have solely analyzed their potential effects on components of kicking performance.

OBJECTIVE

To systematically analyse the influence of warm-up, exercise and/or recovery-related strategies on kicking performance in male soccer players and provide a critical appraisal on research paradigm related to kicking testing constraints and data acquisition methods.

METHODS

A systematic literature search was performed (until July 2020) in PubMed, Web of Science, SPORTDiscus, Scopus and ProQuest. Studies in male soccer populations, which included the effects of warm-up routines, physical exercise and/or recovery-related interventions, reported on comparisons pre-post or between experimental conditions and that computed at least one measure of kicking kinematics and/or performance were considered. Methodological quality and risk of bias were determined for the included studies. Constraints related to kicking testing and data acquisition methods were also summarized and discussed.

RESULTS

Altogether, 52 studies were included. Of these, 10 examined the respective effects of a warm-up, 34 physical exercise, and 21 recovery-related strategies. The results of eight studies showed that lower limb kinematics, kicking accuracy or ball velocity were improved following warm-ups involving dynamic but not static stretching. Declines in ball velocity occurred notably following intermittent endurance or graded until exhaustion exercise (three studies in both cases) without inclusion of any ball skills. In contrast, conflicting evidence in five studies was observed regarding ball velocity following intermittent endurance exercise interspersed with execution of ball skills. Kicking accuracy was less frequently affected by physical exercise (remained stable across 14 of 19 studies). One investigation indicated that consumption of a carbohydrate beverage pre- and mid-exercise demonstrated benefits in counteracting the potentially deleterious consequences of exercise on ball velocity, while four studies reported conflicting results regarding kicking accuracy. Most evidence synthesized for the interventions demonstrated moderate level (77%) and unclear-to-high risk of bias in at least one item evaluated (98%). The main limitations identified across studies were kicks generally performed over short distances (50%), in the absence of opposition (96%), and following experimental instructions which did not concomitantly consider velocity and accuracy (62%). Also, notational-based metrics were predominantly used to obtain accuracy outcomes (54%).

CONCLUSIONS

The results from this review can help inform future research and practical interventions in an attempt to measure and optimise soccer kicking performance. However, given the risk of bias and a relative lack of strong evidence, caution is required when applying some of the current findings in practice.

PROSPERO ID

CRD42018096942.

Preliminary Feasibility Study to Measure the Immediate Changes of Bilateral Asymmetry After Lumbar Spinal Manipulative Therapy in Asymptomatic Athletes

Objective

The purpose of this preliminary study was to assess the feasibility of a study to measure the immediate changes in bilateral asymmetry on physical performance tests before and after lumbar spinal manipulative therapy (SMT).

Methods

Thirteen asymptomatic athletes participated in this study. Each participant underwent a clinical and physical evaluation for inclusion according to eligibility criteria. Assessments were performed in all participants and included a physical test symmetry sequence (static standing position, squat, and countermovement jump) before and after lumbar SMT intervention. The immediate changes were quantitatively measured from before to after intervention by statistical calculations.

Results

All recruited participants completed the study, and none of them reported complaints during participation. Statistically significant differences between before and after lumbar SMT were found only for static symmetry (respectively, mean = 14.4% and 3.7%), not for squatting or the countermovement jump.

Conclusion

According our sample characteristics, asymptomatic athlete participants, presented initially bilateral asymmetry values, such as described in the literature, and after lumbar SMT, these values decreased significantly in static posture. This preliminary study demonstrates the feasibility to measure the pre-to-post changes in symmetry after lumbar SMT intervention. The results showed a great decrease in bilateral symmetry on static symmetry percentage, but none in dynamic tests, which deserves further investigation. Nevertheless, this preliminary study demonstrated the feasibility of measuring the immediate changes in symmetry produced by lumbar SMT, and of a larger study to measure whether lumbar SMT changes symmetry.

The Immediate Effect of Spinal Manipulation on Ball Velocity and Neuromuscular Function During an Instep Kick in Former Varsity Soccer Players: A Feasibility Study

Corso, M, Liang, L, Tran, S, Howitt, S, Srbely, J, and Mior, SA. The immediate effect of spinal manipulation on ball velocity and neuromuscular function during an instep kick in former Varsity soccer players: a feasibility study. J Strength Cond Res XX(X): 000-000, 2020-Spinal manipulation (SM) has been shown to increase ball velocity (BV) in soccer players. Evidence suggests that SM modulates responses at spinal or cortical levels to enhance force production in asymptomatic populations. No studies have explored the underlying neuromuscular mechanisms contributing to changes in BV post-SM in soccer players. We assessed the feasibility of measuring change in BV and neuromuscular function after SM in former Varsity level soccer players with a pre-post study design. Three to 5 maximal instep kicks were performed before and after SM at the L3-5 level. Ball velocity was measured using high-speed camera. Activation of lower limb and trunk musculature was recorded with electromyography. Outcomes included ease of recruitment, scheduling and data capture, as well as expectation and perception of SM effect and adverse events (AE). Fifteen potential subjects were recruited over 1.5 months. Eleven were scheduled (24-31 years; 8 females, 3 males). Two subjects reported mild AE after maximal voluntary isometric contraction testing. A significant increase in BV (mean change: 1.75 m·s [95% confidence interval: 0.5-3.0]) and a trend to increased peak-activation of knee extensors (90.7%) were observed post-SM. Findings suggest that our recruitment strategy and methodology are feasible in a larger trial with some modifications. Our preliminary findings support previous research by suggesting that increased BV may be mediated through increased activation of knee extensors during the kick. Our findings may offer additional insight into the underlying neuromuscular mechanisms contributing to immediate change in BV post-SM.

Predictors of low back disability in chiropractic and physical therapy settings

Background

Predicting ongoing disability for chronic non-specific low back pain (LBP) is important to avoid prolonged disability.

Objective

Determine predictors of disability at 6 month follow-up in patients with LBP at medium risk of ongoing disability.

Methods

Baseline data was collected from 108 patients with medium-risk chronic non-specific LBP (mean age 50.4 years, SD 13.6) from six private chiropractic and physiotherapy clinics in Australia who took part in a randomised control trial. All patients received a pragmatic course of multimodal physical treatments [e.g., manual therapy (spinal manipulation or mobilization and/or soft tissue massage)] combined with advice, education and exercise. Baseline prognostic variables included sociodemographic, physical and psychological characteristics. Primary outcome was disability (Roland Morris Disability) at 6 month follow-up. Multivariable linear regression analysis was conducted.

Results

Variables remaining in the final multivariable model: lower work ability (β = − 1.05, 95% CI − 1.40 to − 0.70; p < 0.0001) and consultation with a medical specialist for back pain in the preceding 3 months (β = 3.35, 95% CI 1.14 to 5.55; p < 0.003), which significantly predicted higher disability at 6 months (unadjusted R ² = 0.31). Those with a lower work ability (scale 1 to 10) and who had seen a medical specialist for their back pain were more likely to report greater LBP-related disability at 6 months.

Conclusion

Patients with chronic LBP presenting to primary care with lower work ability and recent consultation with a medical specialist for LBP are more likely to have a worse prognosis; these are indicators to clinicians that standard conservative care may not adequately manage the patients’ needs.

The effects of spinal manipulation on performance-related outcomes in healthy asymptomatic adult population: a systematic review of best evidence

Introduction

The effectiveness of spinal manipulative therapy (SMT) for improving athletic performance in healthy athletes is unclear. Assessing the effect of SMT on other performance outcomes in asymptomatic populations may provide insight into the management of athletes where direct evidence may not be available. Our objective was to systematically review the literature on the effect of SMT on performance-related outcomes in asymptomatic adults.

Methods

MEDLINE, CINAHL, SPORTDiscus, and Cochrane Central Register of Controlled Trials were systematically searched from 1990 to March 23, 2018. Inclusion criteria was any study examining a performance-related outcome of SMT in asymptomatic adults. Methodological quality was assessed using the SIGN criteria. Studies with a low risk of bias were considered scientifically admissible for a best evidence synthesis. We calculated the between group mean change and 95% confidence intervals.

Results

Of 1415 articles screened, 20 studies had low risk of bias, seven were randomized crossover trials, 10 were randomized controlled trials (RCT) and three were RCT pilot trials. Four studies showed SMT had no effect on physiological parameters at rest or during exercise. There was no effect of SMT on scapular kinematics or transversus abdominus thickness. Three studies identified changes in muscle activation of the upper or lower limb, compared to two that did not. Five studies showed changes in range of motion (ROM). One study showed an increase lumbar proprioception and two identified changes in baropodometric variables after SMT. Sport-specific studies show no effect of SMT except for a small increase in basketball free-throw accuracy.

Conclusion

The preponderance of evidence suggests that SMT in comparison to sham or other interventions does not enhance performance-based outcomes in asymptomatic adult population. All studies are exploratory with immediate effects. In the few studies suggesting a positive immediate effect, the importance of such change is uncertain. Further high-quality performance specific studies are required to confirm these preliminary findings.

Electronic supplementary material

The online version of this article (10.1186/s12998-019-0246-y) contains supplementary material, which is available to authorized users.

Effect of manual therapy versus proprioceptive neuromuscular facilitation in dynamic balance, mobility and flexibility in field hockey players. A randomized controlled trial

OBJECTIVES

To compare the effectiveness of a specific Manual Therapy (MT) protocol applied to field hockey players (FHP), versus a Proprioceptive Neuromuscular Facilitation (PNF) protocol, in the improvement of dynamic balance, active range of movement and lumbar flexibility one-week and four-weeks after the treatment.

DESIGN

Randomized controlled trial. Participants were assigned to 2 groups: MT and PNF. 30 min' sessions were performed once a week for three weeks. Three evaluations were performed: basal, one-week and four-weeks post-treatment.

SETTING

University of Valencia (Spain).

PARTICIPANTS

22 in MT group and 20 in PNF group.

MAIN OUTCOME MEASURES

Dynamic Balance, measured with Star Excursion Balance Test; Active Range of Motion (ROM), using a manual goniometer and Lumbar Flexibility, assessed with Fingertip-to-floor test.

RESULTS

Both groups significantly improved in lateral and medial dynamic balance one-week post-treatment (p < 0.05); but the improvement in the MT group lasted until the fourth-week after treatment in both reaches (lateral and medial) (p < 0.05). MT group also obtained significant improvements in dorsal flexion of the ankle in the fourth-week post-treatment (p < 0.05) and in lumbar flexibility one-week post-treatment (p < 0.05).

CONCLUSIONS

MT and PNF improve dynamic balance one-week post-treatment; however, the improvement obtained through MT is maintained four-weeks later. Only MT improves dorsal flexion of the ankle four-weeks post-treatment and lumbar flexibility one-week post-treatment.

COLLEGIATE MALE SOCCER PLAYERS EXHIBIT BETWEEN-LIMB SYMMETRY IN BODY COMPOSITION, MUSCLE STRENGTH, AND RANGE OF MOTION

Background

Functional and structural asymmetries attributed to limb dominance are equivocal in soccer players. Previous authors hypothesize the existence of between-limb asymmetry secondary to the repetitive unilateral nature of kicking. However, symmetry is often present, particularly in measures of muscle strength.

Purpose

The purpose of the present study was to determine if lateral dominance is accompanied by corresponding between-limb asymmetries in a comprehensive assessment of body composition, muscle strength, and range of motion in healthy soccer players.

Study Design

Cross-sectional, observational.

Methods

17 healthy male NCAA Division One collegiate soccer players participated (age 19.6 ± 1.5 years; BMI 23.9 ± 1.4 kg/m2). Footedness was attained via participant self-report. Lower limb muscle strength (hand held dynamometry), range of motion (goniometry), and body composition (dual energy x-ray absorptiometry scan) were measured. Lower-leg symmetry was analyzed comparing the dominant versus non-dominant limb using paired t-tests.

Results

Comparisons revealed no statistically different differences in outcomes, indicating remarkable symmetry in all measures of body composition, muscle strength, and range of motion (p>0.05) between the dominant and non-dominant lower limbs.

Conclusions

The authors speculate the prevalence of running versus kicking, the longitudinal effects of playing careers, and/or functional compensation attenuates the expected asymmetries in healthy male collegiate soccer players.

Level of Evidence

2b.

Spinal Manipulative Therapy and Sports Performance Enhancement: A Systematic Review

OBJECTIVE

The purpose of this study was to review the literature regarding the relationship between spinal manipulative therapy (SMT) and sports performance.

METHODS

PubMed and Embase databases were searched for original studies published up to July 2016. Inclusion criteria were if SMT has been applied to athletes and if any sports performance-related outcome was measured.

RESULTS

Of the 581 potential studies, 7 clinical trials were selected. Most studies had adequate quality (≥6/11) when assessed by the PEDro scale. None of those studies assessed performance at an event or competition. Four studies revealed improvement in a sports performance test after SMT. Meta-analysis could not be performed because of the wide differences in methodologies, design, and outcomes measured. Spinal manipulative therapy influences a wide range of neurophysiological parameters that could be associated with sports performance. Of the 3 studies where SMT did not improve test performance, 2 used SMT not for therapeutic correction of a dysfunctional vertebral joint but to an arbitrary previously set joint.

CONCLUSIONS

Although 4 of 7 studies showed that SMT improved sports performance tests, the evidence is still weak to support its use. Spinal manipulative therapy may be a promising approach for performance enhancement that should be investigated with more consistent methodologic designs.