Background: Sedentary behavior (SB) is associated with several chronic diseases and office workers especially are at increased risk. SB is defined by a sitting or reclined body posture with an energy expenditure of ≤1.5 metabolic equivalents. However, current objective methods to measure SB are not consistent with its definition. There is no consensus on which sensor placement and type should be used. Aim: To compare the accuracy of newly developed artificial intelligence models for 15 sensor placements in combination with four signal types (accelerometer only/plus gyroscope and/or magnetometer) to detect posture and physical in-/activity during desk-based activities. Method: Signal features for the model development were extracted from sensor raw data of 30 office workers performing 10 desk-based tasks, each lasting 5 min. Direct observation (posture) and indirect calorimetry (in-/activity) served as the reference criteria. The best classification model for each sensor was identified and compared among the sensor placements, both using Friedman and post hoc Wilcoxon tests (p ≤ .05). Results: Posture was most accurately measured with a lower body sensor, while in-/activity was most accurately measured with an upper body or waist sensor. The inclusion of additional signal types improved the posture classification for some placements, while the acceleration signal already contained the relevant signal information for the in-/activity classification. Overall, the thigh accelerometer most accurately classified desk-based SB. Conclusion: This study favors, in line with previous work, the measurement of SB with a thigh-worn accelerometer and adds the information that this sensor is also accurate in measuring physical in-/activity while sitting and standing.
Roman P. Kuster, Daniel Baumgartner, Maria Hagströmer and Wilhelmus J.A. Grooten
Liana M. Tennant, Erika Nelson-Wong, Joshua Kuest, Gabriel Lawrence, Kristen Levesque, David Owens, Jeremy Prisby, Sarah Spivey, Stephanie R. Albin, Kristen Jagger, Jeff M. Barrett, James D. Wong and Jack P. Callaghan
Spinal stiffness and mobility assessments vary between clinical and research settings, potentially hindering the understanding and treatment of low back pain. A total of 71 healthy participants were evaluated using 2 clinical assessments (posteroanterior spring and passive intervertebral motion) and 2 quantitative measures: lumped mechanical stiffness of the lumbar spine and local tissue stiffness (lumbar erector spinae and supraspinous ligament) measured via myotonometry. The authors hypothesized that clinical, mechanical, and local tissue measures would be correlated, that clinical tests would not alter mechanical stiffness, and that males would demonstrate greater lumbar stiffness than females. Clinical, lumped mechanical, and tissue stiffness were not correlated; however, gradings from the posteroanterior spring and passive intervertebral motion tests were positively correlated with each other. Clinical assessments had no effect on lumped mechanical stiffness. The males had greater lumped mechanical and lumbar erector spinae stiffness compared with the females. The lack of correlation between clinical, tissue, and lumped mechanical measures of spinal stiffness indicates that the use of the term “stiffness” by clinicians may require reevaluation; clinicians should be confident that they are not altering mechanical stiffness of the spine through segmental mobility assessments; and greater resting lumbar erector stiffness in males suggests that sex should be considered in the assessment and treatment of the low back.
Behnam Gholami-Borujeni, Ali Yalfani and Leila Ahmadnezhad
This study was conducted to evaluate the effects of 8-week inspiratory muscle training on activity in the ankle muscles of athletes with chronic low-back pain. A randomized controlled trial involving 45 men and women with chronic low-back pain was carried out. Electromyography activity in the tibialis anterior, peroneus longus, gastrocnemius medialis, and gastrocnemius lateralis muscles of the dominant leg was recorded. Secondary outcomes included biopsychosocial indices, such as pain, disability, anxiety and depression, fear-avoidance beliefs, and fear of (re)injury. Static and dynamic overhead squat tests showed that inspiratory muscle training decreased activity in the tibialis anterior, peroneus longus, and gastrocnemius medialis muscles. In the static single-leg squat test and the descending phase of the dynamic equivalent, such a decrease was observed in all the 4 muscles. Inspiratory muscle training significantly reduced pain severity and activity in the tibialis anterior, peroneus longus, and gastrocnemius medialis muscles during the ascending phase of the dynamic single-leg squat test. On the basis of the findings, 8 weeks of inspiratory muscle training may constitute useful rehabilitation for reducing excessive activity in ankle joint muscles and aiding chronic low-back pain recovery.
Marcin Straczkiewicz, Nancy W. Glynn, Vadim Zipunnikov and Jaroslaw Harezlak
Background: The increasing popularity of wrist-worn accelerometers introduces novel challenges to the research on physical activity and sedentary behavior. Estimation of body posture is one such challenge. Methods: The authors proposed an approach called SedUp to differentiate between sedentary (sitting/lying) and standing postures. SedUp is based on the logistic regression classifier, using the wrist elevation and the motion variability extracted from raw accelerometry data collected on the axis parallel to the forearm. The authors developed and tested our method on data from N = 45 community-dwelling older adults. All subjects wore ActiGraph GT3X+ accelerometers on the left and right wrist, and activPAL was placed on the thigh in the free-living environment for 7 days. ActivPAL provided ground truth about body posture. The authors reported SedUp’s classification accuracy for each wrist separately. Results: Using the data from the left wrist, SedUp estimated the standing posture with median true positive rate = 0.83 and median true negative rate = 0.91. Using the data from the right wrist, SedUp estimated the standing posture with median true positive rate = 0.86 and median true negative rate = 0.93. Conclusions: SedUp provides accurate classification of body posture using wrist-worn accelerometers. The separate validation for each wrist allows for the application of SedUp in a wide spectrum of free-living studies.
Justin B. Hollander, Ann Sussman, Peter Lowitt, Neil Angus and Minyu Situ
Background: Understanding more about the unseen side of our responses to visual stimuli offers a powerful new tool for transportation planning. Traditional transportation planning tends to focus on the mobility of vehicles rather than on opportunities to encourage sustainable transport modes, like walking. Methods: Using eye-tracking emulation software, this study measured the unconscious visual responses people have to designs and layouts in new built environments, focusing on what makes streets most walkable. Results: The study found key differences between the way the brain takes in conventional automobile-oriented residential developments versus new urbanist layouts, with the former lacking key fixation points. Conclusion: The study’s discoveries significantly explain why new urbanist layouts promote walking effortlessly and conventional automobile-oriented residential developments cannot.
Geeta Sharma, Tom Stewart and Scott Duncan
Background: Curriculum-integrated dance programs are a promising but relatively under-researched strategy for increasing children’s physical activity (PA). The aim of this study was to determine the impact of a curriculum-integrated dance program on children’s PA. Methods: A total of 134 primary children aged 7–9 years from 4 New Zealand schools were assigned to either a dance group (n = 78) or a control group (n = 56). The dance group participated in a 6-week curriculum-integrated dance program during school time. Although the dance program focused on curricular learning, fitness and coordination were embedded in the dance sessions. Intensity of PA varied according to the focus of each dance session. PA was measured at baseline and postintervention using a waist-mounted ActiGraph GT3X+ accelerometer for 8 consecutive days. Results: There were no significant intervention effects on PA levels between the dance and control groups postintervention. Conclusion: Dance-embedded learning did not increase overall levels of PA in this study. Future studies may consider assessing longer term effects of a dance-based intervention, or programs that place more focus on PA promotion.
Ángel Luis Clemente Remón, Víctor Jiménez Díaz-Benito, José Emilio Jiménez Beatty and José Antonio Santacruz Lozano
The study aimed to ascertain the levels of older European people’s physical activity according to sociodemographic variables. The sample size was 7,893 citizens aged 65 and over from the European Union. The participants were classified as physically inactive, adequately active, or highly active, according to the World Health Organization. The total metabolic equivalents of task minutes per week were also calculated. In the results, 55.5% of older people were adequately active, and 43.8% were highly active, especially in the North and West. The average metabolic equivalents of task minutes per week was 1,313 metabolic equivalents of task minutes, with walking as the main activity, followed by moderate physical activity and vigorous activity. Male older people of a lower age from the North and West, with a higher level of education and less difficulty in paying bills, were more likely to be physically active. As a conclusion, only slightly more than half the population were adequately active. These sociodemographic inequalities show the necessity of implementing specific measures.
Jarle Stålesen, Thomas Westergren, Bjørge Herman Hansen and Sveinung Berntsen
Background: Smartphones with embedded sensors, such as accelerometers, are promising tools for assessing physical activity (PA), provided they can produce valid and reliable indices. The authors aimed to summarize studies on the PA measurement properties of smartphone accelerometers compared with research-grade PA monitors or other objective methods across the intensity spectrum, and to report the effects of different smartphone placements on the accuracy of measurements. Methods: A systematic search was conducted on July 1, 2019 in PubMed, Embase, SPORTDiscus, and Scopus, followed by screening. Results: Nine studies were included, showing moderate-to-good agreements between PA indices derived from smartphone accelerometers and research-grade PA monitors and/or indirect calorimetry. Three studies investigated measurement properties across smartphone placements, with small differences. Large heterogeneity across studies hampered further comparisons. Conclusions: Despite moderate-to-good agreements between PA indices derived from smartphone accelerometers and research-grade PA monitors and/or indirect calorimetry, the validity of smartphone monitoring is currently challenged by poor intermonitor reliability between smartphone brands/versions, heterogeneity in protocols used for validation, the sparsity of studies, and the need to address the effects of smartphone placement.
Alfonso Gutiérrez-Santiago, Iván Prieto-Lage, Arturo Martín and Carlos Ayán
Background: To provide information regarding injury incidence, injury pattern, and associated injury risk factors in elite Paralympic judokas. Methods: Participants in this observational research were elite judokas taking part in the IBSA 2018 World Judo Championship. The entire championship was videotaped, and all injuries were prospectively documented using an all-complaints definition. Results: The tournament featured 267 judokas, (B1 = 58; B2 = 105; B3 = 104). The injury proportion was estimated at 18.9 injuries/100 fighters (B1 = 13.8; B2 = 22.3; B3 = 18.5). A total of 745 athletic exposures were registered. The overall injury rate was 68.5 (95% CI, 52.5–89.2); 62.5 (95% CI, 32–122.3); 79.6 (95% CI, 53.8–17.8); and 61.2 (95% CI, 40–93.5) for the total sample, B1, B2, and B3 judokas, respectively. When only injuries resulting in medical attention were analyzed, the overall injury rate was calculated to be 22.8 (95% CI, 14.3–36.5), and the injury proportion was estimated at 6.3 injuries/100 fighters. No significant differences were found for sex, weight, and visual class regarding injury proportion and injury rates. Conclusion: Paralympic judokas show a high injury rate. However, when only injuries that needed medical attention were taken into account, the proportion of athletes injured was low. The degree of visual impairment was not considered as an injury risk factor.
Jeanette M. Ricci, Todd A. Astorino, Katharine D. Currie and Karin A. Pfeiffer
The majority of studies examining children’s responses to high-intensity interval exercise primarily utilized running; however, this modality does not require/include other important aspects of physical activity including muscular fitness. Purpose: To compare acute responses between a body weight resistance exercise circuit (CIRC) and treadmill-based (TM) high-intensity interval exercise. Method: A total of 17 boys (age = 9.7 [1.3] y) completed a graded exercise test to determine peak heart rate, peak oxygen uptake (VO2peak), and maximal aerobic speed. Sessions were randomized and counterbalanced. CIRC required 2 sets of 30-second maximal repetitions of 4 exercises. TM included eight 30-second bouts of running at 100% maximal aerobic speed. Both included 30-second active recovery between bouts. Blood lactate concentration was measured preexercise and postexercise. Rating of perceived exertion, affective valence, and enjoyment were recorded preexercise, after intervals 3 and 6, and postexercise. Results: Participants attained 88% (5%) peak heart rate and 74% (9%) VO2peak for CIRC and 89% (4%) peak heart rate and 81% (6%) VO2peak for TM, with a significant difference in percentage of VO2peak (P = .003) between protocols. Postexercise blood lactate concentration was higher following CIRC (5.0 [0.7] mM) versus TM (2.0 [0.3] mM) (P < .001). Rating of perceived exertion, affective valence, and enjoyment responses did not differ between protocols (P > .05). Conclusion: HR responses were near maximal during CIRC, supporting that this body-weight circuit is representative of high-intensity interval exercise.