Vasculoprotective properties of plasma lipoproteins from brown bears (Ursus arctos).

Plasma cholesterol and triglyceride (TG) levels are twice as high in hibernating brown bears (Ursus arctos) than healthy humans. Yet, bears display no signs of early stage atherosclerosis development when adult. To explore this apparent paradox, we analyzed plasma lipoproteins from the same 10 bears in winter (hibernation) and summer using size exclusion chromatography, ultracentrifugation, and electrophoresis. LDL binding to arterial proteoglycans (PGs) and plasma cholesterol efflux capacity (CEC) were also evaluated. The data collected and analyzed from bears were also compared with those from healthy humans. In bears, the cholesterol ester, unesterified cholesterol, TG, and phospholipid contents of VLDL and LDL were higher in winter than in summer. The percentage lipid composition of LDL differed between bears and humans but did not change seasonally in bears. Bear LDL was larger, richer in TGs, showed prebeta electrophoretic mobility, and had 5-10 times lower binding to arterial PGs than human LDL. Finally, plasma CEC was higher in bears than in humans, especially the HDL fraction when mediated by ABCA1. These results suggest that in brown bears the absence of early atherogenesis is likely associated with a lower affinity of LDL for arterial PGs and an elevated CEC of bear plasma.

Cervico-thoracic pain and associated impairments in air force personnel: a cross-sectional study.

BACKGROUND: Pain and impaired function in the cervical region are common in Air Force personnel (AFP), but evidence is limited regarding the thoracic region. This cross-sectional cohort study examined associations between cervico-thoracic pain and physical performance among Swedish AFP and explored possible differences and similarities in test performance between fighter pilots (FP), helicopter pilots (HP) and rear crew (RC). METHODS: AFP (n = 73) from one airbase performed eight tests of movement control of the spine, active cervical range of motion (ROM) in all six directions and isometric strength and endurance of the cervical flexors and extensors. The association between test performance and cervico-thoracic pain (based on the 'Musculoskeletal screening protocol' questionnaire) were analysed in a multiple binary logistic regression model. RESULTS: For AFP with cervico-thoracic pain (30%), movement control was impaired in the 'neck flexion test' (OR [95%CI] =3.61 [1.06-12.34]) and the 'forward lean test' (OR [95%CI] =3.43[1.04-11.37]), together with reduced flexion ROM (OR [95%CI] =0.93 [0.87-0.99]). Test performance was in general similar between the three groups, but FP and HP could control the 'forward lean test' to a significantly higher degree than RC (p = 0.000). Further, FP showed significantly greater ROM in lateral flexion to the right compared to HP and RC (mean: 40.3°, 36.2° and 33.4°, respectively, p = 0.000), and they showed higher, although not significant, flexor strength than RC (p = 0.026). CONCLUSIONS: The impaired function associated with cervico-thoracic pain highlights the need for a deeper understanding of such relationships when designing tools to systematically optimize the physical performance and prevent pain among AFP. Studies with a longitudinal design are warranted to examine any causative associations between pain and impairments.

Musculoskeletal disorders and their associations with health- and work-related factors: a cross-sectional comparison between Swedish air force personnel and army soldiers.

BACKGROUND: The high numbers of musculoskeletal disorders (MSD) among soldiers in the Swedish Armed Forces has led to the implementation of an effective prevention program, the musculoskeletal screening protocol (MSP), including questionnaires, physical tests and individual intervention of their MSD. A corresponding MSP for the Swedish Air Force is also needed due to earlier reported high prevalence of MSD. We therefore investigated the prevalence of MSD in Swedish Air Force personnel (AF) and compared this to Swedish Army deployed soldiers (DS). Individual, health- and work-related factors associated with MSD were also investigated. METHODS: Cross-sectional questionnaire-based study on 166 male AF and 185 DS. AF consisted of fighter pilots, helicopter pilots and rear crew from one Swedish air base. RESULTS: The one-year and point prevalence, respectively, of MSD were significantly higher for AF compared to DS with regard to both the upper quarter of the body (i.e. neck, shoulder and thoracic regions) (AF = 54.8 and 31.3%, DS = 26.1 and 13.6%, p = 0.01) and the lumbar region (AF = 38.0 and 18.7%, DS = 22.2 and 7.1%, p = 0.00). No significant differences were present between fighter pilots, helicopter pilots and rear crew regarding MSD prevalence. Factors significantly associated with having both upper quarter and lumbar regions MSD were group (i.e. greater odds for AF than DS) and self-reported physical health as less than excellent. Additionally, being older and taller were also factors associated with lumbar region MSD. DISCUSSION: Despite a generally healthy lifestyle, MSD were commonly reported by AF and DS, with generally higher prevalence in AF who mainly reported MSD in the upper quarter of the body. The results from this study indicate that the MSP can be a meaningful tool to prevent MSD in air force personnel and that questions regarding general health and MSD in specific body regions should be included in screening protocols. The development of the preventive program MSP is therefore recommended for the Swedish Air Force.

Correction to: Musculoskeletal disorders and their associations with health- and work-related factors: a cross-sectional comparison between Swedish air force personnel and army soldiers.

An amendment to this paper has been published and can be accessed via the original article.

Content Validity Index and Reliability of a New Protocol for Evaluation of Lifting Technique in the Powerlifting Squat and Deadlift.

Sjöberg, H, Aasa, U, Rosengren, M, and Berglund, L. Content validity index and reliability of a new protocol for evaluation of lifting technique in the powerlifting squat and deadlift. J Strength Cond Res 34(9): 2528-2536, 2020-The aim of the study was to create a protocol to cover aspects of technique considered to be associated with risk of injury in the powerlifting squat and deadlift and to examine the content validity and reliability of the aspects included in the protocols. For the content validity investigation, a consensus group of 3 powerlifting physiotherapists identified the domains of content (risk of injury) for 2 protocols (1 for squat and 1 for deadlift) of essential aspects of lifting technique through discussions and a review of the literature. Eight selected powerlifting experts rated the relevance of each aspect in relation to risk of injury (acute or by overuse), and a quantitative estimate of the content validity of each aspect was measured through calculations of a Content Validity Index (CVI). Aspects of low content validity were discarded, and the remainders were evaluated for their inter-rater and intra-rater reliability among 4 experienced powerlifters used to coaching and evaluating powerlifting technique. The reliability was calculated and analyzed with kappa and percentage of agreement. The final protocols included 17 aspects of squat technique and 10 aspects of deadlift technique that showed good to excellent CVI and percentage of agreement between 64 and 100%. The protocols, formed in this study, will provide evidence-based recommendations on safe lifting technique for coaches and strength practitioners' to use to make relevant assessments and instructions.

Injuries among weightlifters and powerlifters: a systematic review.

BACKGROUND: Olympic weightlifting and powerlifting are two sports that expose the body to great forces. Injury characteristics have not been systematically reviewed for these two growing sports. OBJECTIVE: The purpose of this study was to systematically review the literature regarding various definitions of injuries used, injury localisation, the prevalence and incidence of injuries and the associated risk factors for injuries in weightlifting and powerlifting. DESIGN: Systematic review. DATA SOURCES: Five databases, PubMed, MEDLINE, SPORTDiscus, Scopus and Web of Science, were searched between 9 March and 6 April 2015. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Studies assessing injury incidence and prevalence in Olympic weightlifting and powerlifting were included. The Quality assessment tool for observational cohort and cross-sectional studies was used to assess methodological quality. RESULTS: 9 studies were included in the review. Injury was defined fairly consistently across studies. Most studies were of low methodological quality. The spine, shoulder and the knee were the most common injury localisations in both sports. The injury incidence in weightlifting was 2.4-3.3 injuries/1000 hours of training and 1.0-4.4 injuries/1000 hours of training in powerlifting. Only one retrospective study had analysed possible risk factors. SUMMARY/CONCLUSIONS: The risk of injury in both sports were similar to other non-contact sports also requiring strength/power, but low compared to contact sports. The severity of injuries differed in the included studies. Since little has been studied regarding possible risk factors to injuries, further research is therefore warranted to explain why athletes get injured and how to prevent injuries. TRIAL REGISTRATION NUMBER: PROSPERO CRD42015014805.

Correspondence Between Physical Self-Concept and Participation in, and Fitness Change After, Biweekly Body Conditioning Classes in Sedentary Women.

Aasa, U, Paulin, J, and Madison, G. Correspondence between physical self-concept and participation in, and fitness change after, biweekly body conditioning classes in sedentary women. J Strength Cond Res 31(2): 451-461, 2017-The aims of the study were (a) to investigate the effects of participation in low impact body conditioning classes on physical fitness in sedentary women at different ages and (b) to examine the correspondence between physical self-concept and participation in, and fitness change after, the participation. Ninety-two sedentary women (mean age 44.2 years) participated in 11 weeks of biweekly classes that included cardiovascular, strength, core, endurance, and mobility exercises, all performed in synchrony with music. Cardiorespiratory fitness, maximal lifting strength, mobility, and balance tests were performed before and after the exercise period and the short-form of the Physical Self-Description Questionnaire (PSDQ-S) was completed. Zero-order Spearman correlation analyses showed that women who rated the PSDQ-S dimension sport competence higher participated in a larger number of sessions (rs = 0.24, p = 0.040). At posttests, all participants had increased their balance, the participants aged 20-34 years had increased their lifting strength, and the participants aged 35-65 years had increased their cardiorespiratory fitness and mobility. Most PSDQ-S dimensions did not affect performance change, but the perception of being physically active was related to increased cardiovascular fitness. We conclude that women with a sedentary lifestyle who wish to increase their physical capacity benefit from music exercise and that inquiries about perceived sport competence and physical activity can improve recommendations made by strength and conditioning professionals.

Which Patients With Low Back Pain Benefit From Deadlift Training?

Recent studies have indicated that the deadlift exercise may be effective in decreasing pain intensity and increasing activity for most, but not all, patients with a dominating pattern of mechanical low back pain. This study aimed to evaluate which individual factors measured at baseline could predict activity, disability, and pain intensity in patients with mechanical low back pain after an 8-week training period involving the deadlift as a rehabilitative exercise. Thirty-five participants performed deadlift training under the supervision of a physical therapist with powerlifting experience. Measures of pain-related fear of movement, hip and trunk muscle endurance, and lumbopelvic movement control were collected at baseline. Measures of activity, disability, and pain intensity were collected at baseline and at follow-up. Linear regression analyses were used to create models to predict activity, disability, and pain intensity at follow-up. Results showed that participants with less disability, less pain intensity, and higher performance on the Biering-Sørensen test, which tests the endurance of hip and back extensor muscles, at baseline benefit from deadlift training. The Biering-Sørensen test was the most robust predictor because it was included in all predictive models. Pain intensity was the next best predictor as it was included in 2 predictive models. Thus, for strength and conditioning professionals who use the deadlift as a rehabilitative exercise for individuals with mechanical low back pain, it is important to ensure that clients have sufficient back extensor strength and endurance and a sufficiently low pain intensity level to benefit from training involving the deadlift exercise.

Shoulder and forearm oxygenation and myoelectric activity in patients with work-related muscle pain and healthy subjects.

We tested hypotheses of (a) reduced oxygen usage, oxygen recovery, blood flow and oxygen consumption; and (b) increased muscle activity for patients diagnosed with work-related muscle pain (WRMP) in comparison to healthy controls. Oxygenation was measured with near infrared spectroscopy (NIRS), and muscle activity with EMG for the extensor carpi radialis (ECR) and trapezius descendens (TD) muscles. Eighteen patients with diffuse neck-shoulder-arm pain and 17 controls (matched in age and sex) were equipped with NIRS and EMG probes. After determining an individual's maximum voluntary contraction (MVC) force, short-term (20 s) isometric contractions for the ECR and TD of 10, 30, 50 and 70 % MVC generated ∆StO2 and StO2% recovery (Rslope) from NIRS, and RMS%max from EMG signals. In addition, upper arm venous (VO) and arterial (AO) occlusions generated slopes of total hemoglobin (HbTslope) and deoxyhemoglobin (HHbslope) for the resting ECR as surrogates of blood flow and oxygen consumption, respectively. Mixed model analyses, t tests, and Mann-Whitney test were used to assess differences between groups. There was no significant difference in MVC between groups for either muscle. Also, ∆StO2%, Rslope for either muscle, and ECR-HbTslope were not different between groups, thus our hypotheses of reduced oxygen use, recovery, and blood flow for patients were not confirmed. However, patients had a significantly lower ECR-HHbslope confirming our hypothesis of reduced consumption. Further, there was no difference in RMS%max during contractions meaning that the hypothesis of increased activity for patients was not confirmed. When taking into account the number of NIRS variables studied, differences we found between our patient group and healthy controls (i.e., in forearm oxygen consumption and shoulder oxygen saturation level) may be considered modest. Overall our findings may have been impacted by the fact that our patients and controls were similar in muscle strength, which is in contrast to previous studies.

A Prospective Cohort Study on Risk Factors for Cervico-Thoracic Pain in Military Aircrew.

BACKGROUND: Military aircrew frequently report cervico-thoracic pain and injury. The relationship between risk factors and future pain episodes is, however, uncertain. The aim of this study was to identify risk factors for cervico-thoracic pain and to determine the 1-yr cumulative incidence of such pain.METHODS: A total of 47 Swedish aircrew (fighter and helicopter pilots and rear crew) without pain in the cervico-thoracic region were surveyed about work-related and personal factors and pain prevalence using the Musculoskeletal Screening Protocol questionnaire. They also performed tests of movement control, active cervical range of motion, and isometric neck muscle strength and endurance. Aircrew were followed for a year with questionnaires. Logistic regressions were used to identify potential risk factors for future cervico-thoracic pain.RESULTS: Previous cervico-thoracic pain (OR: 22.39, CI: 1.79-280.63), lower cervical flexion range of motion (OR: 0.78, CI: 0.64-0.96), and lower neck flexor muscular endurance (OR: 0.91, CI: 0.83-0.99) were identified as risk factors for reporting cervico-thoracic pain. At follow-up, 23.4% (CI: 13.6-37.2) had reported cervico-thoracic pain during the 12-mo follow-up period.DISCUSSION: The Musculoskeletal Screening Protocol can identify risk factors for cervico-thoracic pain. The link between cervico-thoracic pain and previous pain, as well as lower performance of neck range of motion and muscular endurance, highlights the need for primary and secondary preventive action. The findings from this study can facilitate the development of such pain prevention programs for aircrew.Tegern M, Aasa U, Larsson H. A prospective cohort study on risk factors for cervico-thoracic pain in military aircrew. Aerosp Med Hum Perform. 2023; 94(7):500-507.

Thoracolumbar and Lumbopelvic Spinal Alignment During the Barbell Back Squat: A Comparison Between Men and Women.

Background: Maintaining neutral spinal alignment is considered important when performing the barbell back squat exercise. Since male and female lifters may differ in injury location it is important to examine whether they differ in spinal alignment during the back squat. Objectives: The study aimed to quantify the spinal alignment in the upper and lower lumbar spine during the barbell back squat exercise in male and female lifters. Secondary aims were to compare alignment during the back squat to standing habitual lumbar spine alignment and determine whether male and female lifters differ in these aspects. Study Design: Observational, Cross-sectional. Methods: Competitive power- and weightlifters were recruited and performed three repetitions of the barbell back squat exercise using a load equivalent to 70% of their one-repetition maximum. Spinal alignment and range of motion were measured using inertial measurement units placed on the thoracic, lumbar and sacral spine. Data was presented descriptively and comparisons between men and women as well as spinal alignment in four different positions were done with a factorial repeated measures analysis of variance. Results: Twenty-three (14 males, 9 females) were included. During execution of the squat, spinal alignment adjustments in the lumbar spine were made in all three planes of movement, compared to the start position, in both male and female lifters. Compared to their standing habitual posture, all lifters adjusted their upper lumbar spine to a less lordotic position when in the start position of the back squat (standing upright with the barbell on their back). Only male lifters assumed a less lordotic alignment in their lower lumbar spine in the start position compared their habitual posture. Conclusions: Adjustments of spinal alignment, predominantly in the sagittal plane, are made during execution of the back squat in both male and female lifters. Further, lifters adopt a less lordotic alignment with a heavy barbell on their upper back, more so in male than female lifters. In conclusion, it seems that spinal alignment changes noticeably during the barbell back squat. Level of Evidence: 3©The Author(s).

Textile electromyography electrodes reveal differences in lower limb muscle activation during loaded squats when comparing fixed and free barbell movement paths.

Introduction: Traditional recordings of muscle activation often involve time-consuming application of surface electrodes affixed to the skin in laboratory environments. The development of textile electromyography (EMG) electrodes now allows fast and unobtrusive assessment of muscle activation in ecologically valid environments. In this study, textile EMG shorts were used to assess whether performing squats with the barbell resting freely on the shoulders or using a Smith machine for a fixed barbell movement path is preferable for maximizing lower limb muscle activation. Methods: Sixteen athletes performed free and fixed barbell squats in a gym with external loads equivalent to their body mass. Quadriceps, hamstrings and gluteus maximus activation was measured bilaterally with textile EMG electrodes embedded in shorts. Results: Mean quadriceps activation was greater for the free compared with the fixed movement path for the right (mean difference [MD] 14µV, p = 0.04, ηp 2 = 0.28) and left leg (MD 15µV, p = 0.01, ηp 2 = 0.39) over the entire squat and specifically during the first half of the eccentric phase for the left leg (MD 7µV, p = 0.04, d = 0.56), second half of the eccentric phase for both legs (right leg MD 21µV, p = 0.05, d = 0.54; left leg MD 23µV, p = 0.04, d = 0.52) and the first half of the concentric phase for both legs (right leg MD 24µV, p = 0.04, d = 0.56; left leg MD 15µV, p = 0.01, d = 0.72). Greater hamstrings activation for the free path was seen for the second half of the eccentric phase (left leg MD 4µV, p = 0.03, d = 0.58) and first half of the concentric phase (right leg MD 5µV, p = 0.02, d = 0.72). No significant differences were found for gluteus maximus. Discussion: Textile EMG electrodes embedded in shorts revealed that to maximize thigh muscle activity during loaded squats, a free barbell movement path is preferable to a fixed barbell movement path.

Thoracolumbar And Lumbopelvic Spinal Alignment During The Deadlift Exercise: A Comparison Between Men And Women.

Background: A neutral spinal alignment is considered important during the execution of the deadlift exercise to decrease the risk of injury. Since male and female powerlifters experience pain in different parts of their backs, it is important to examine whether men and women differ in spinal alignment during the deadlift. Objectives: The purpose of this study was to quantify the spinal alignment in the upper (thoracolumbar, T11-L2) and lower (lumbopelvic, L2-S2) lumbar spine during the deadlift exercise in male and female lifters. Secondary aims were to compare lumbar spine alignment during the deadlift to standing habitual posture, and determine whether male and female lifters differ in these aspects. Study Design: Observational, Cross-sectional. Methods: Twenty-four (14 men, 10 women) lifters performed three repetitions of the deadlift exercise using 70% of their respective one-repetition maximum. Spinal alignment and spinal range of motion were measured using three inertial measurement units placed on the thoracic, lumbar and sacral spine. Data from three different positions were analyzed; habitual posture in standing, and start and stop positions of the deadlift, i.e. bottom and finish position respectively. Results: During the deadlift, spinal adjustments were evident in all three planes of movement. From standing habitual posture to the start position the lumbar lordosis decreased 13° in the upper and 20° in the lower lumbar spine. From start position to stop position the total range of motion in the sagittal plane was 11° in the upper and 22° in the lower lumbar spine. The decreased lumbar lordosis from standing habitual posture to the start position was significantly greater among men. Conclusions: Men and women adjust their spinal alignment in all three planes of movement when performing a deadlift and men seem to make greater adjustments from their standing habitual posture to start position in the sagittal plane. Level of Evidence: 3.

Variability of lumbar spinal alignment among power- and weightlifters during the deadlift and barbell back squat.

The aims of the study were to evaluate the relative and absolute variability of upper (T11-L2) and lower (L2-S2) lumbar spinal alignment in power- and weightlifters during the deadlift and back squat exercises, and to compare this alignment between the two lifting groups. Twenty-four competitive powerlifters (n = 14) and weightlifters (n = 10) performed three repetitions of the deadlift and the back squat exercises using a load equivalent to 70% of their respective one-repetition maximum. The main outcome measures were the three-dimensional lumbar spinal alignment for start position, minimum and maximum angle of their spinal alignment, and range of motion measured using inertial measurement units. Relative intra-trial reliability was calculated using the two-way random model intraclass correlation coefficient (ICC) and absolute reliability with minimal detectable change (MDC). The ICC ranged between 0.69 and 0.99 and the MDC between 1°-8° for the deadlift. Corresponding figures for the squat were 0.78-0.99 and 1°-6°. In all participants during both exercises, spinal adjustments were made in both thoracolumbar and lumbopelvic areas in all three dimensions. In conclusion, when performing three repetitions of the deadlift and the squat, lumbar spinal alignment of the lifters did not change much between repetitions and did not differ significantly between power- and weightlifters.

How accurate are visual assessments by physical therapists of lumbo-pelvic movements during the squat and deadlift?

OBJECTIVES: To investigate the accuracy of visual assessments made by physical therapists of lumbo-pelvic movements during the squat and deadlift and how much movement is considered injurious. DESIGN: Quantitative Cross-sectional. PARTICIPANTS: 14 powerlifters, 10 Olympic weightlifters and six physical therapists. SETTING: The lifters were recorded simultaneously by video and an inertial measurement unit (IMU) system while performing squats and deadlifts. The physical therapists assessed the videos and rated whether specific lumbo-pelvic movements were visible during the lifts and whether the movement amplitude was considered injurious. MAIN OUTCOME MEASURES: The nominal visual assessments, if there was a movement and if it was considered injurious, were compared to the degrees of movement attained from the IMU system. RESULTS: During the squat, a posterior pelvic tilt of ≥34° was required to visually detect the movement. For other lumbo-pelvic movements, there was no significant difference in the amount of movement between those who were assessed as moving or not moving their lumbo-pelvic area, nor was there a difference in movement amplitude between those who were assessed as having an increased risk of injury or not. CONCLUSIONS: Physical therapists did not consistently detect lumbo-pelvic movements during squats and deadlifts when performed by competitive lifters.

A descriptive analysis of functional impairments and patho-anatomical findings in eight powerlifters.

BACKGROUND: Low back pain (LBP) is a common pain problem in powerlifters. There is a lack of evidence to guide powerlifters and health-care professionals in understanding the role of powerlifting in the development of LBP and treatment of injuries in powerlifters. This study aimed to describe functional impairments and patho-anatomical findings in eight powerlifters with and without LBP. METHODS: First, four powerlifters with LBP were recruited. Each powerlifter was then matched with a pain-free lifter (Control) by age, Body Mass Index and competition weight class. They all performed physical performance tests and were examined with magnetic resonance imaging. Four weeks prior to the examination the powerlifters also recorded training load. Powerlifters with LBP were also examined by a physiotherapist in order to define their pain and impairments. RESULTS: The four male powerlifters with LBP had a nociceptive pain associated with non-ideal squatting technique, higher flexibility in their lumbar spine than in their hips and patho-anatomical findings such as degenerated discs (four), spondylolysis (one) and spinal stenosis (one). However, the controls also showed similar functional impairments and patho-anatomical findings. CONCLUSIONS: Powerlifters with and without LBP show similar functional impairments and patho-anatomical findings. However, powerlifters' LBP seems associated with pain during movement and loading of the lumbar spine. The association and causation between specific functional impairments, patho-anatomical findings and LBP in powerlifters has to be further investigated in studies including more participants.

Health care in light of different theories of health-A proposed framework for integrating a social humanistic perspective into health care.

The objective of this paper is to provide an overview of the biomedical, the biopsychosocial, and the social humanistic theories of health and to propose a framework for integrating the latter into health care. In summary, the definitions of health, illness and disease are essential to the practice of health care and play fundamental roles in how patients' experiences of being ill are valued and assessed within health care systems. Principally, the biomedical perspective proceeds from pathoanatomical deficiencies defining disease and malfunction; the addition of psychosocial components forms a biopsychosocial perspective. In addition, the social humanistic perspective extends from a person's will, their ability to act, and the possibility to fulfill wanted actions. Thus, health care that does not address the social humanistic perspective may lack the power to describe how these entities are related to the patient on a personal level; thus, the will of the patient is not always fully addressed. Importantly, by targeting the will of the patient and the patient's ability to act, the proposed framework of integrating a social humanistic perspective into health care may further emphasize and strengthen the interrelatedness of medical perspectives. A framework for integrating a social humanistic perspective into health care is proposed and its potential impact on health care is discussed.

Narrative review of injuries in powerlifting with special reference to their association to the squat, bench press and deadlift.

Pain and injuries are considered a common problem among elite athletes and recreational lifters performing the squat, bench press and deadlift. Since all three lifts engage multiple joints and expose the lifters' bodies to high physical demands often several times a week, it has been suggested that their injuries might be related to the excessively heavy loads, the large range of motion during the exercises, insufficient resting times between training sessions and/or faulty lifting technique. However, no previous article has summarised what is known about specific injuries and the injury aetiology associated with the three lifts. Thus, the aim of this narrative review was to summarise what is known about the relationships between the powerlifting exercises and the specific injuries or movement impairments that are common among lifters and recreationally active individuals.

Sagittal lumbopelvic alignment in patients with low back pain and the effects of a high-load lifting exercise and individualized low-load motor control exercises-a randomized controlled trial.

BACKGROUND CONTEXT: Assessment of posture and lumbopelvic alignment is often the main focus in the classification and treatment of patients with low back pain (LBP). However, little is known regarding the effects of motor control interventions on objective measures of lumbopelvic alignment. PURPOSE: The primary aim of this study was to describe the variation of sagittal lumbopelvic alignment in patients with nociceptive mechanical LBP. The secondary aim was to compare the effects of a high-load lifting exercise (HLL) and low-load motor control exercises (LMC) on the change in lumbopelvic alignment with a special emphasis on patients with high and low degrees of lumbar lordosis (lu) and sacral angle (sa). STUDY DESIGN: This study is a secondary analysis of a randomized controlled trial evaluating the effects of HLL and LMC. PATIENT SAMPLE: Patients from the primary study, that is, patients categorized with nociceptive mechanical LBP, who agreed to participate in the radiographic examination were included (n=66). OUTCOME MEASURES: Lateral plain radiographic images were used to evaluate lumbopelvic alignment regarding the lumbar lordosis and the sacral angle as outcomes, with posterior bend as an explanatory variable. MATERIALS AND METHODS: The participants were recruited to the study from two occupational health-care facilities. They were randomized to either the HLL or the LMC intervention group and offered 12 supervised exercise sessions. Outcome measures were collected at baseline and following the end of intervention period 2 months after baseline. Between- and within-group analyses of intervention groups and subgroups based on the distribution of the baseline values for the lumbar lordosis and the sacral angle, respectively (LOW, MID, and HIGH), were performed using both parametric and non-parametric statistics. RESULTS: The ranges of values for the present sample were 26.9-91.6° (M=59.0°, standard deviation [SD]=11.5°) for the lumbar lordosis and 18.2-72.1° (M=42.0°, SD=9.6°) for the sacral angle. There were no significant differences between the intervention groups in the percent change of eitheroutcome measure. Neither did any outcome change significantly over time within the intervention groups. In the subgroups, based on the distribution of respective baseline values, LOWlu showed a significantly increased lumbar lordosis, whereas HIGHsa showed a significantly decreased sacral angle following intervention. CONCLUSIONS: This study describes the wide distribution of values for lumbopelvic alignment for patients with nociceptive mechanical LBP. Further research is needed to investigate subgroups of other types of LBP and contrast findings to those presented in this study. Our results also suggest that retraining of the lumbopelvic alignment could be possible for patients with LBP.

Prevalence and Consequences of Injuries in Powerlifting: A Cross-sectional Study.

BACKGROUND: Powerlifting consists of the squat, bench press, and dead lift, and extreme loads are lifted during training and competitions. Previous studies, which have defined an injury as an event that causes an interruption in training or competitions, have reported a relatively low frequency of powerlifting injuries (1.0-4.4 injuries/1000 hours of training). No previous study has investigated the prevalence of injuries, defined as a condition of pain or impairment of bodily function that affects powerlifters' training, in a balanced sample of men and women, and no studies have established possible risk factors for an injury. PURPOSE: To investigate the prevalence, localization, and characterization of injuries among Swedish subelite classic powerlifters, with an emphasis on differences between men and women, and to investigate whether training and lifestyle factors are associated with an injury. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A total of 53 female and 51 male Swedish subelite powerlifters answered an online questionnaire including questions about background characteristics, training habits, and lifestyle factors. The main part of the questionnaire included questions about injuries and their consequences. An injury was defined as a condition of pain or impairment of bodily function that affects powerlifters' training. RESULTS: Seventy percent (73/104) of participants were currently injured, and 87% (83/95) had experienced an injury within the past 12 months. The lumbopelvic region, shoulder, and hip were the most commonly injured areas for both sexes. Women experienced a significantly greater frequency of injuries in the neck and thoracic region than men. Injuries seemed to occur during training, although only 16% (11/70) of those currently injured had to completely refrain from training. Training frequency, greater personal best in the dead lift, injury onset during bench-press and dead-lift training, use of straps, alcohol consumption, and dietary issues were associated with current injuries. CONCLUSION: Injuries are very common in subelite powerlifters. Men and women report similar injury frequencies but different anatomic locations. These injuries do not prevent powerlifters from training and competing, but they may change the content of training sessions. Why powerlifters develop injuries is still unclear; however, it is likely that the management of training loads and optimization of the lifting technique during the squat, bench press, and dead lift are of importance.