Anton Westman

Effectiveness of motivational interviewing and physical activity on prescription on leisure exercise time in subjects suffering from mild to moderate hypertension

BackgroundPhysical inactivity is considered to be the strongest individual risk factor for poor health in Sweden. It has been shown that increased physical activity can reduce hypertension and the risk of developing cardiovascular diseases. The objective of the present pilot study was to investigate whether a combination of Motivational Interviewing (MI) and Physical Activity on Prescription (PAP) would increase leisure exercise time and subsequently improve health-related variables.MethodsThis pilot study was of a repeated measures design, with a 15 months intervention in 31 patients with mild to moderate hypertension. Primary outcome parameter was leisure exercise time and secondary outcome parameters were changes in blood pressure, Body Mass Index (BMI), waist circumference, lipid status, glycosylated haemoglobin (HbA1c) and maximal oxygen uptake (VO2 max). Assessments of the outcome parameters were made at baseline and after 3, 9 and 15 months.ResultsLeisure exercise time improved significantly from < 60 min/week at baseline to a mean activity level of 300 (± 165) minutes/week at 15 months follow up. Furthermore, statistically significant improvements (p < 0.05) were observed in systolic (-14,5 ± 8.3 mmHg) and diastolic blood pressure (-5,1 ± 5.8 mmHg), heart rate (-4.9 ± 8.7 beats/min, weight (-1.2 ± 3.4 kg) BMI -0.6 ± 1.2 kg/m2), waist circumference (-3.5 ± 4.1 cm) as well as in VO2 max (2.94 ± 3.8 ml/kg and 0.23, ± 0.34 lit/min) upon intervention as compared to baseline.ConclusionsA 15 month intervention period with MI, in combination with PAP, significantly increased leisure exercise time and improved health-related variables in hypertensive patients. This outcome warrants further research to investigate the efficacy of MI and PAP in the treatment of mild to moderate hypertension.

Fatalities in wingsuit BASE jumping.

OBJECTIVE To analyze fatality data associated with wingsuit use in an international case series of fixed-object sport parachuting (BASE jumping) to identify incident and injury mechanisms and to form a basis for potential prevention measures and future safety recommendations. METHODS A descriptive epidemiological study was performed of fatal injury events occurring in wingsuit BASE jumping. Fatalities (n = 180) were sequentially analyzed assessing human, equipment, and environmental factors from 1981 to 2011. Main outcome measures included descriptions of typical fatal incident and injury mechanisms. RESULTS Of the 180 fatal events, 39 (22%) were related to use of wingsuits; 38 (97%) launched from cliffs and 1 (3%) from a building. Of the 39 fatalities, 19 (49%) were caused from cliff strikes, 18 (46%) from ground impact, and 1 (3%) from a building strike. Thirty-eight (97%) of the fatalities were male. During 2002 to 2007 there was a total of 61 BASE jumping deaths, 10 (16%) of which were related to the use of wingsuits, whereas during 2008 to 2011 there was a total 59 fatal events, of which 29 (49%) were related to the use of wingsuits. Seventeen fatalities (39%) were attributed to wingsuit path miscalculation. In the first 8 months of 2013, 17 of 19 (90%) fatalities were wingsuit related. Most fatalities occurred between April and October, reflecting a seasonal increase in activity in the northern hemisphere summer. CONCLUSIONS Wingsuit-related BASE jump fatalities appear to be increasing as wingsuit BASE jumping increases in popularity. Most fatalities are attributed to cliff or ground impact, and are mostly the result of flying path miscalculation.

Musculoskeletal pain and related risks in skydivers: A population-based survey

INTRODUCTION Sport parachuting from aircraft (skydiving) is a major aerial activity in which parachutists are subject to decelerating forces during parachute opening shock (POS), possibly as much as 3-5 G. While traumatic incidents related to POS have been reported, epidemiological data on musculoskeletal pain among skydivers is absent in the literature. The aim was therefore to examine the prevalence of self-rated musculoskeletal pain related to POS in a skydiver population and elicit related risk factors. METHODS There were 658 Swedish sport skydivers who completed a structured web-based questionnaire (70% response rate; email invitation) validated for use in skydivers. The questionnaire concerned individual and skydiving-related risk indicators, and musculoskeletal pain experiences. Multiple regression analysis was used to estimate the relationship between risk indicators and musculoskeletal pain related to POS. RESULTS The 12-mo prevalence of musculoskeletal pain related to POS was highest for the neck region, 25% (95% CI = 21.4-28.2). Other upper-body regions were as follows: shoulder 16% thoracic spine 10%, and lower back 18%. A high number of parachute jumps in the last 12 mo, i.e., 30-90 jumps (RR = 1.7, 95% CI = 1.1-2.7), > 90 jumps (RR = 2.1, 95% CI = 1.3-3.4), and a high main parachute wing-loading, i.e., > 1.4 lb/ft2 (RR = 1.7, 95% CI = 1.1-2.6) were independent risk factors. CONCLUSIONS Neck pain related to POS was common among skydivers. A high number of parachute jumps the last 12 mo and high wing-loading emerged as risk factors, suggesting that highly active skydivers using small canopies may be at risk. Studies on biomechanics under POS are suggested.

Neck muscle activity in skydivers during parachute opening shock.

This observational study investigated skydiver neck muscle activity during parachute opening shock (POS), as epidemiological data recently suggested neck pain in skydivers to be related to POS. Twenty experienced skydivers performed two terminal velocity skydives each. Surface electromyography quantified muscle activity bilaterally from the anterior neck, the upper and lower posterior neck, and the upper shoulders; and two triaxial accelerometers sampled deceleration. Muscle activity was normalized as the percentage of reference maximum voluntary electrical activity (% MVE); and temporal muscle activity onset was related to POS onset. Our results showed that neck muscle activity during POS reached mean magnitudes of 53–104% MVE, often exceeding reference activity in the lower posterior neck and upper shoulders. All investigated muscle areas’ mean temporal onsets occurred <50 ms after POS onset (9–34 ms latencies), which is consistent with anticipatory motor control. The high muscle activity observed supports that the neck is under substantial strain during POS, while temporal muscle activation suggests anticipatory motor control to be a strategy used by skydivers to protect the cervical spine from POS. This studys findings contribute to understanding the high rates of POS‐related neck pain, and further support the need for evaluation of neck pain preventative strategies.

Decelerations and muscle responses during parachute opening shock.

INTRODUCTION Pain in the neck region among skydivers can be related to repeated parachute opening shocks (POS), but empirical data on ramair POS biomechanics is lacking in the literature. The aim of this study was to develop and evaluate a methodology for assessment of multidirectional accelerations and neck muscle activity during parachuting, and to describe preliminary data. METHODS In an experimental design, four experienced skydivers made two consecutive skydives. Deceleration was recorded with two triaxial accelerometers, one placed on the skydivers cervicothoracic junction (acc-neck) and the other on the harness (acc-rig). Surface electromyography (EMG) was sampled from four sites bilaterally: anterior-neck, posterior upper and lower neck, and upper shoulder muscles. EMG activity was normalized against a premeasured maximum voluntarily produced electrical signal (MVE). RESULTS The measuring equipment did not interfere with the parachute jumps. High-quality signals were recorded. The median peak POS deceleration for the acc-neck vs. acc-rig indicated differences (4.0 G vs. 5.1 G), in addition to significant differences emerging for medians of average and maximum onset rates of deceleration (avg: 1.2 G x s(-1) vs. 19.5 G x s(-1); max: 23.0 G x s(-1) vs. 80.0 G x s(-1)). The median of overall muscleactivity was as high as 87% MVE, but no differences in peak activity were found between muscles. Temporal activations of the posterior upper neck occurred less than 50 ms after deceleration initiation, indicating feedforward control of the neck. CONCLUSION All instruments recorded data of good quality without impeding the skydiving activity. Triaxial accelerometry on the neck vs. the harness yielded dissimilar results, underlining the importance of correct accelerometer placement. Muscle activity was high during POS and neck muscles showed anticipatory tendencies.

Validation of a free fall acrobatics intervention protocol to reduce neck loads during parachute opening shock

Background Elevated neck pain prevalence among skydivers is associated with exposure to repeated parachute opening shock (POS). A study is planned to evaluate a preventive free fall acrobatics intervention, but prior assessment of the protocol is necessary given the complex and safety-critical study environment. Aim To validate an intervention protocol to reduce POS neck loads. Methods A protocol was developed based on observational data and theoretical calculations. Six experts rated each component of the protocol on a four-point Likert scale, regarding relevance, simplicity/feasibility and safety, and responded to open-ended questions. Two iterations were made, each followed by consensus panel protocol revisions. The content validity index (CVI) was used to quantify ratings. A measure of universal agreement (CVI/UA) was computed as the proportion of components that achieved a rating ≥3 by all raters. For safety, a high-sensitivity CVI/UA was computed with a rating of no <4 (highest score) as acceptable. Results CVI/UA for relevance increased from 0.80 in the first assessment to 1.00 in the second; for simplicity from 0.50 to 0.63; and for safety from 0.70 to 1.00. High-sensitivity CVI/UA for safety increased from 0.10 to 0.75. Responses to open-ended questions included safety concerns for free fall stability, altitude awareness and concerns over comprehensibility. Conclusions The proposed protocol has been improved in assessed relevance, simplicity and safety, and is considered validated for the start of the empirical trial. To what degree complex interventions should be preceded by open prevalidation is discussed.

Neck muscle EMG-force relationship and its reliability during isometric contractions

BackgroundSusceptible to injury, the neck is subject to scientific investigations, frequently aiming to elucidate possible injury mechanisms via surface electromyography (EMG) by indirectly estimating cervical loads. Accurate estimation requires that the EMG-force relationship is known and that its measurement error is quantified. Hence, this study examined the relationship between EMG and isometric force amplitude of the anterior neck (AN), the upper posterior neck (UPN), and the lower posterior neck (LPN) and then assessed the relationships’ test-retest reliability across force-percentiles within and between days.MethodsEMG and force data were sampled from 18 participants conducting randomly ordered muscle contractions at 5–90% of maximal voluntary force during three trials over 2 days. EMG-force relationships were modeled with general linear mixed-effects regression. Overall fitted lines’ between-trial discrepancies were evaluated. Finally, the reliability of participants’ fitted regression lines was quantified by an intraclass correlation coefficient (ICC) and the standard error of measurement (SEM).ResultsA rectilinear model had the best fit for AN while positively oriented quadratic models had the best fit for UPN and LPN, with mean adjusted conditional coefficients of determination and root mean square errors of 0.97–0.98 and 4–5%, respectively. Overall EMG-force relationships displayed a maximum 6% between-trial discrepancy and over 20% of maximal force, and mean ICC was above 0.79 within day and 0.27–0.61 between days across areas. Corresponding SEM was below 12% both within and between days across areas, excluding UPN between days, for which SEM was higher.ConclusionsEMG-force relationships were elucidated for three neck areas, and provided models allow inferences to be drawn from EMG to force on a group level. Reliability of EMG-force relationship models was higher within than between days, but typically acceptable for all but the lowest contraction intensities, and enables adjustment for measurement imprecision in future studies.

BASE Jumping and Wingsuit Flying Injuries

In this chapter, the main features of BASE jumping and wingsuits flying are discussed, focusing in particular on those aspects which mainly influence risk, such as equipment, exiting, and jumped objects.

Pilots and Diabetes Technology: Functional Health

Diabetes technology is not only of help for patients to live a close to normal life from a medical point of view, it is also of important benefit when it comes to their professional lives. People with diabetes are active in (nearly) all jobs that exist. However, there are certain professions that are prohibited for them—but only in certain countries. Though the job and its setting may be identical, some countries prohibit people with diabetes from employment, while others do not. These international incoherencies are related to different types of diabetes as well as diabetes therapy, and appear to lack a clear medical rationale. One poignant example is the professional piloting of aircraft. Flying an airplane is a highly demanding task. To enter this profession, an individual must meet all of a number of requirements regarding skills, knowledge and medical fitness. After more than 100 years of professional flying, it would seem that these requirements should by now be well validated and internationally harmonized. Any changes brought by advances in aircraft technology or, as in the case of diabetes, medical therapy, should induce similar responses in national certification legislations. To our understanding, this is not the case. Different countries or regions (eg, the European Aviation Safety Agency) have different rules as to which planes a pilot is allowed to fly when she or he has diabetes, in some countries only cargo planes, in other all planes. The regulatory incoherencies extend to whether a given patient has already a pilot license before diagnosed (typically patients with type 2 diabetes) or if she or he has diabetes already when applying for a pilot license (typically patients with type 1 diabetes). It would also seem of relevance if the pilots are private or commercial pilots, if they intend to fly a doubleor single-command airplane, and so on. In other words, there appears to be a lack of international harmonization for this job, even though it is international in its occupational setting, and there appears to be a lack of understanding of the necessary stratifications of the issue. In the United States, the Federal Aviation Administration (FAA) does not allow medical certificates for people who use insulin to operate commercial aircraft, although they can apply for a third-class medical certificate, which allows them to perform private and recreational operations and fly as student pilots, flight instructors, or sport pilots. The ADA is currently “developing recommendations to share with the US FAA that would enable the FAA to identify pilots who are at no greater risk for incapacitation than any other pilot,” according to the association’s position statement. The ADA opposes a “blanket ban” and instead takes the position that individual assessment of people with diabetes is the appropriate approach to determining whether a person is qualified to perform certain activities. We fully agree with this position and will outline why we believe this is the right way to go. What is the rationale for maintaining so diverse rules? Again we have to say, there are few studies/little data substantiating the current situation. It appears as if the rules are driven by the personal opinions of the physicians (in the best case, probably others are also involved) and their diabetes knowledge. Therefore, much of the following discussion also holds true for physicians that regulate car traffic or other working conditions. The regulations for patients with diabetes that have a driving license or want to get one, are quite diverse between countries and dependent on whether they drive only themselves or want to drive a cab or a bus. This difference in how diabetes is regarded becomes obvious when it comes to the International Statistical Classification of Diseases and Related Health Problems (ICD) and the International Classification of Functioning, Disability and Health (ICF). Physicians in most countries are familiar with coding of diseases in ICD codes as this is relevant for their honorarium. This in turn has also an impact on the way she or he thinks. A patient with diabetes is thereby 680510 DSTXXX10.1177/1932296816680510Journal of Diabetes Science and TechnologyJendle et al editorial2016

Decelerations of Parachute Opening Shock in Skydivers

INTRODUCTION High prevalence of neck pain among skydivers is related to parachute opening shock (POS) exposure, but few investigations of POS deceleration have been made. Existing data incorporate equipment movements, limiting its representability of skydiver deceleration. This study aims to describe POS decelerations and compare human- with equipment-attached data. METHODS Wearing two triaxial accelerometers placed on the skydiver (neck-sensor) and equipment (rig-sensor), 20 participants made 2 skydives each. Due to technical issues, data from 35 skydives made by 19 participants were collected. Missing data were replaced using data substitution techniques. Acceleration axes were defined as posterior to anterior (+ax), lateral right (+ay), and caudal to cranial (+az). Deceleration magnitude [amax (G)] and jerks (G · s-1) during POS were analyzed. RESULTS Two distinct phases related to skydiver positioning and acceleration direction were observed: 1) the x-phase (characterized by -ax, rotating the skydiver); and 2) the z-phase (characterized by +az, skydiver vertically oriented). Compared to the rig-sensor, the neck-sensor yielded lower amax (3.16 G vs. 6.96 G) and jerk (56.3 G · s-1 vs. 149.0 G · s-1) during the x-phase, and lower jerk (27.7 G · s-1 vs. 54.5 G · s-1) during the z-phase. DISCUSSION The identified phases during POS should be considered in future neck pain preventive strategies. Accelerometer data differed, suggesting human-placed accelerometry to be more valid for measuring human acceleration.Gladh K, Lo Martire R, Äng BO, Lindholm P, Nilsson J, Westman A. Decelerations of parachute opening shock in skydivers. Aerosp Med Hum Perform. 2017; 88(2):121-127.