-
Hypertension (Dallas, Tex. : 1979) Jan 2024Abnormal orthostatic blood pressure (BP) regulation may result in cerebral hypoperfusion and brain ischemia and contribute to dementia. It may also manifest as early...
BACKGROUND
Abnormal orthostatic blood pressure (BP) regulation may result in cerebral hypoperfusion and brain ischemia and contribute to dementia. It may also manifest as early symptoms of the neurodegenerative process associated with dementia. The relationship between the magnitude and timing of orthostatic BP responses and dementia risk is not fully understood.
METHODS
We conducted a prospective cohort analysis of the associations of orthostatic BP changes and self-reported orthostatic dizziness with the risk of dementia in the Atherosclerosis Risk in Communities study (ARIC). We calculated changes in BP from the supine to the standing position at 5 measurements taken within 2 minutes after standing during the baseline visit (1987-1989). The primary outcome was adjudicated dementia ascertained through 2019.
RESULTS
Among 11 644 participants (mean [SD] age, 54.5 [5.7] years; 54.1% women; 25.9% Black), 2303 dementia cases were identified during a median follow-up of 25.9 years. Large decreases in systolic BP from the supine to standing position measured at the first 2 measurements ≈30 and 50 seconds after standing, but not afterward, were associated with orthostatic dizziness and a higher risk of dementia. Comparing a decrease in systolic BP of ≤-20 or >-20 to -10 mm Hg to stable systolic BP (>-10 to 10 mm Hg) at the first measurement, the adjusted hazard ratios were 1.22 (95% CI, 1.01-1.47) and 1.10 (95% CI, 0.97-1.25), respectively.
CONCLUSIONS
Abnormal orthostatic BP regulation, especially abrupt drops in BP within the first minute, might be early risk markers for the development of dementia. Transient early orthostatic hypotension warrants more attention in clinical settings.
Topics: Humans; Female; Middle Aged; Male; Dizziness; Blood Pressure; Standing Position; Prospective Studies; Hypotension, Orthostatic; Hypotension; Atherosclerosis; Dementia
PubMed: 37869909
DOI: 10.1161/HYPERTENSIONAHA.123.21438 -
International Journal of Environmental... Oct 2023In the past decade, university students have become more sedentary. A sedentary lifestyle is associated with an increased risk of obesity and cardiovascular disease....
In the past decade, university students have become more sedentary. A sedentary lifestyle is associated with an increased risk of obesity and cardiovascular disease. Methods that decrease sedentary lifestyles, such as the use of standing desks to increase physical activity, have been extensively examined. However, the effects of postprandial standing and sitting on energy metabolism have not yet been compared. Therefore, the present study investigated the effects of standing after a meal on energy expenditure and glucose metabolism. Ten males participated in the present study. The experiment was initiated with 300 g of rice ingested as a carbohydrate load. The subjects maintained a standing or sitting position for 120 min after the meal. Energy expenditure was calculated from VO and VCO using the indirect calorimetry method. Glucose metabolism was assessed by measuring blood glucose levels and the exogenous glucose metabolic rate. Energy expenditure through standing after eating was approximately 0.16 ± 0.08 kcal/min higher than that through sitting. Blood glucose dynamics did not significantly differ between the standing and sitting positions. Furthermore, no significant differences were observed in the dynamics of the exogenous glucose metabolic rate between the standing and sitting positions. Standing for 2 h after a meal increased energy expenditure by 10.7 ± 4.6% without affecting glucose metabolism.
Topics: Male; Humans; Blood Glucose; Energy Metabolism; Standing Position; Obesity; Sitting Position
PubMed: 37887672
DOI: 10.3390/ijerph20206934 -
PloS One 2023Emotion recognition is key to interpersonal communication and to human-machine interaction. Body expression may contribute to emotion recognition, but most past studies...
Emotion recognition is key to interpersonal communication and to human-machine interaction. Body expression may contribute to emotion recognition, but most past studies focused on a few motions, limiting accurate recognition. Moreover, emotions in most previous research were acted out, resulting in non-natural motion, which is unapplicable in reality. We present an approach for emotion recognition based on body motion in naturalistic settings, examining authentic emotions, natural movement, and a broad collection of motion parameters. A lab experiment using 24 participants manipulated participants' emotions using pretested movies into five conditions: happiness, relaxation, fear, sadness, and emotionally-neutral. Emotion was manipulated within subjects, with fillers in between and a counterbalanced order. A motion capture system measured posture and motion during standing and walking; a force plate measured center of pressure location. Traditional statistics revealed nonsignificant effects of emotions on most motion parameters; only 7 of 229 parameters demonstrate significant effects. Most significant effects are in parameters representing postural control during standing, which is consistent with past studies. Yet, the few significant effects suggest that it is impossible to recognize emotions based on a single motion parameter. We therefore developed machine learning models to classify emotions using a collection of parameters, and examined six models: k-nearest neighbors, decision tree, logistic regression, and the support vector machine with radial base function and linear and polynomial functions. The decision tree using 25 parameters provided the highest average accuracy (45.8%), more than twice the random guess for five conditions, which advances past studies demonstrating comparable accuracies, due to our naturalistic setting. This research suggests that machine learning models are valuable for emotion recognition in reality and lays the foundation for further progress in emotion recognition models, informing the development of recognition devices (e.g., depth camera), to be used in home-setting human-machine interactions.
Topics: Humans; Emotions; Standing Position; Fear; Happiness; Walking
PubMed: 37703239
DOI: 10.1371/journal.pone.0290564 -
Annals of Geriatric Medicine and... Dec 2023Considering concerns about conventional toe grip strength, we devised a method to measure toe pressure strength in the standing position, which is close to the actual...
BACKGROUND
Considering concerns about conventional toe grip strength, we devised a method to measure toe pressure strength in the standing position, which is close to the actual motion. This study examined the association between toe pressure strength in the standing position and walking speed among older adults.
METHODS
This cross-sectional study included 150 community-dwelling older adults (81±8 years, 73% female) who participated in the physical fitness test. We analyzed the correlation between the participants' maximum walking speed and physical function. Furthermore, we performed regression analysis with the maximum walking speed as the dependent variable to examine the association with toe pressure strength in the standing position. We also examined the association between maximum walking speed and toe pressure strength in the standing position by introducing a covariate.
RESULTS
Correlation analysis revealed a significant positive correlation between maximum walking speed and toe pressure strength in the standing position, with a moderate effect size (r=0.48, p<0.001). Moreover, multiple regression analysis with covariates showed an association between maximum walking speed and toe pressure strength in the standing position (standardization factor=0.13, p<0.026).
CONCLUSION
Toe pressure strength in the standing position was associated with maximum walking speed. This finding clarifies the significance of assessing toe pressure strength in the standing position and suggests that enhanced toe pressure strength in the standing position may increase maximum walking speed.
PubMed: 37743683
DOI: 10.4235/agmr.23.0113 -
International Journal of Environmental... May 2024Children functioning at Gross Motor Function Classification System (GMFCS) levels IV-V cannot maintain an aligned standing position or take steps without support....
Children functioning at Gross Motor Function Classification System (GMFCS) levels IV-V cannot maintain an aligned standing position or take steps without support. Upright positioning and mobility devices have psycho-social significance for these children and their families, enhancing use of vision, communication, functioning and emotional well-being. Standers and supported stepping devices facilitate opportunities for biomechanical loading, potentially helping to build and maintain muscle and bone integrity, and they promote physical development. However, families are often required to choose between these two devices for their young child. This study aims to synthesize evidence for use and benefits of both supported standing and stepping devices through the lens of two contemporary theoretical frameworks to support clinical reasoning and implementation. The F-words for childhood development (functioning, family, fitness, fun, friends, future) and the interdependence-Human Activity Assistive Technology (iHAAT) models were combined to illustrate the complex interactions between the child, family, caregivers, peers and contextual factors when implementing standing and stepping devices with children at GMFCS levels IV and V. Supported standing and stepping devices provide complementary benefits, and both may be necessary starting at 9-15 months. We propose they both be included ON-Time, along with other age-appropriate positioning and mobility devices, to promote more equitable developmental opportunities for children with non-ambulant cerebral palsy.
Topics: Child; Child, Preschool; Humans; Cerebral Palsy; Self-Help Devices; Standing Position
PubMed: 38928915
DOI: 10.3390/ijerph21060669 -
Disability and Rehabilitation.... Nov 2023There are no manually propelled wheelchairs on the market that are mobile in both seated and standing positions. In response to this product gap, our group formerly...
PURPOSE
There are no manually propelled wheelchairs on the market that are mobile in both seated and standing positions. In response to this product gap, our group formerly designed a mobile manual standing wheelchair (MMSW) and gathered stakeholder feedback. The purpose of this study was to refine the MMSW based on feedback, including weight and width reduction, and evaluate its performance.
MATERIALS AND METHODS
The MMSW was subjected to ANSI/RESNA stability testing, and three male participants completed a subset of the wheelchair skills test, including a 100-m roll test in the MMSW (seated and standing) and in their ultralight wheelchair.
RESULTS
The MMSW met ANSI/RESNA stability safety standards. During the 100-m roll test, participants reached speeds with the MMSW in both the standing and sitting postures similar or greater than those typical of moving in the home environment (1.11 m/s seated; 0.79 m/s standing). Mobility speeds in the MMSW in the standing position were about three times faster than average walking speeds in exoskeletons (0.26 m/s exoskeletons). With the addition of chain drive bracing to the MMSW, one user was able to reach speeds in the standing position similar to average neurotypical walking speeds indicating the possibility for wheelchair users to be able to move in pace with family and friends.
CONCLUSION
All participants expressed interest in the MMSW to facilitate improved quality of life. Further work is needed to test the utility of the MMSW in home and community settings, and its potential effects on standing time and health outcomes.Implications for rehabilitationManual standing wheelchairs with standing mobility may increase functional utility and length of standing time for manual wheelchair usersIncreased standing time may lead to several health benefits for manual wheelchair users.
Topics: Humans; Male; Standing Position; Quality of Life; Equipment Design; Wheelchairs; Braces
PubMed: 35196472
DOI: 10.1080/17483107.2022.2041737 -
Clinical Biomechanics (Bristol, Avon) Oct 2023Limited research has focused on older prosthesis users despite the expected compounded effects of age and amputation on sensorimotor function, balance, and falls. This... (Observational Study)
Observational Study
BACKGROUND
Limited research has focused on older prosthesis users despite the expected compounded effects of age and amputation on sensorimotor function, balance, and falls. This study compared sensorimotor factors and standing balance between older individuals with and without transtibial amputation, hypothesizing that prosthesis users would demonstrate worse sensorimotor function. Secondarily we assessed the relationship between standing balance and somatosensation in prosthesis users.
METHODS
Thirteen persons with unilateral transtibial amputation (71.7 years) and 10 able-bodied controls (71.7 years) participated in this cross-sectional observational study. Passive joint range-of-motion, muscle strength, proprioception (joint position sense), tactile sensitivity, and standing balance (center-of-pressure sway) were compared between groups. A multiple linear regression analysis assessed the relationship between proprioception and balance (without vision) in prosthesis users.
FINDINGS
Our hypotheses were generally not supported, with the only differences being reduced joint range-of-motion and strength in prosthesis users (with large effect sizes), but comparable sensation and balance. Notably, prosthesis users demonstrated better proprioception than controls as reflected through better joint position sense when the limb was non-weight bearing. Worse amputated limb proprioception was associated with better standing balance in prosthesis users.
INTERPRETATION
Older prosthesis users have impaired passive joint motion and muscle strength compared to controls that could challenge their ability to position and control the amputated limb to avoid falls during daily activities. However, their better amputated limb proprioception might help counteract those limitations by leveraging sensory feedback from the suspended limb. The relationship between amputated limb proprioception and standing balance suggests a nuanced relationship that warrants further study.
Topics: Humans; Aged; Cross-Sectional Studies; Postural Balance; Amputees; Proprioception; Amputation, Surgical; Artificial Limbs
PubMed: 37757679
DOI: 10.1016/j.clinbiomech.2023.106104 -
Perceptual and Motor Skills Dec 2023Mechanical vibration of the Achilles tendon is widely used to analyze the role of proprioception in postural control. The response to this tendon vibration (TV) has been...
Mechanical vibration of the Achilles tendon is widely used to analyze the role of proprioception in postural control. The response to this tendon vibration (TV) has been analyzed in the upright posture, but the feet positions have varied in past research. Moreover, investigators have addressed only temporal parameters of the center of pressure (CoP). We investigated the effect of TV on both temporal and spectral characteristics of the CoP motion. Eighteen healthy young adults, stood barefoot, with one foot on each side of a dual platform, wearing glasses with opaque lenses. We applied 20 seconds of Achilles TV (bilaterally with inertial vibrators at a frequency of 80 Hz and an amplitude of .2-.5 mm). We analyzed CoP signals pre-vibration (PRE,4-seconds), during vibration (VIB,20 seconds), and after vibration cessation (REC,20 seconds). We repeated this protocol in natural and standardized positions (15° feet angular opening). For determining CoP amplitude and velocity, we divided the 20 seconds into five phases of four seconds each and calculated spectral parameters for the whole 20-second signals. There was an adaptation process in the speed of the CoP mediolateral ( < .01) and anteroposterior ( < .01) and in the displacement of the CoP anteroposterior ( < .01), with higher values in the VIB condition. Velocity and displacement decreased progressively in the REC condition. Median and peak frequencies were higher in the VIB condition when compared to the REC condition, but only in the mediolateral direction ( = .01). The standardized foot position led to increased speed in CoP mediolateral, anteroposterior, and mediolateral displacement ( < .01). CoP spectral characteristics were not affected by foot positioning. We concluded that adaptation of CoP motion in the presence of TV and after its cessation are observable both in time and frequency domains. Feet positioning influenced CoP motion in the presence of TV and after its cessation but it did not affect its spectral characteristics.
Topics: Young Adult; Humans; Achilles Tendon; Vibration; Proprioception; Postural Balance; Standing Position
PubMed: 37654231
DOI: 10.1177/00315125231198161 -
Scientific Reports Sep 2023Current guidelines recommend office blood pressures (BP) be taken in a seated position when screening for hypertension (HTN). Seated BP is known to have limited accuracy...
Current guidelines recommend office blood pressures (BP) be taken in a seated position when screening for hypertension (HTN). Seated BP is known to have limited accuracy in detecting high BP, while the utility of standing BP in diagnosing HTN is unknown. We conducted a cross-sectional study to determine the incremental value of standing BP in diagnosing HTN. Seated, standing, and 24-h ambulatory BPs (ABPM) were obtained in adults without known cardiovascular disease, HTN, or BP medication use. Presence of HTN was defined by the 2017 ACC/AHA and the 2023 ESH HTN guidelines based on ABPM. Area under the receiver-operating-characteristic curve (AUROC) was used to evaluate the diagnostic accuracy of seated and standing BP. Sensitivity and specificity of standing BP was determined using cut-offs derived from Youden's Index, while sensitivity and specificity of seated BP was determined using the cut-off of 130/80 mmHg and by 140/90 mmHg. Among 125 participants (mean age 49 ± 17 years; 62% female; 24% Black), 33.6% of them had HTN. Sensitivity and specificity of seated systolic BP (SBP) was 43% and 92%, respectively. Cut-offs selected by Youden's index for standing SBP/diastolic BP (DBP) were 124/81 mmHg according to the 2017 ACC/AHA HTN guidelines, and 123.5/83.5 mmHg according to the 2023 ESH HTN guidelines. Sensitivity and specificity of standing SBP was 71% and 67%, respectively. The AUROC of standing SBP (0.81 [0.71-0.92]) was significantly higher than seated SBP (0.70 [0.49-0.91]), when HTN was defined as average 24-h SBP ≥ 125 mmHg. Moreover, the addition of standing to seated SBP (0.80 [0.68-0.92]) improved HTN detection when compared to seated SBP. These patterns were consistent for both the 2017 ACC/AHA and the 2023 ESH definitions for HTN. In summary, standing BP, alone or in combination with seated BP, outperformed seated BP alone in diagnosing HTN in adults.
Topics: Humans; Adult; Female; Middle Aged; Aged; Male; Blood Pressure; Cross-Sectional Studies; Hypertension; Cardiovascular Diseases; Area Under Curve
PubMed: 37730821
DOI: 10.1038/s41598-023-42297-6 -
Aesthetic Surgery Journal Oct 2023Standardized photographic recording and anatomic evaluation are crucial to refined and comprehensive preoperative design and enhanced aesthetic effect of female genital...
BACKGROUND
Standardized photographic recording and anatomic evaluation are crucial to refined and comprehensive preoperative design and enhanced aesthetic effect of female genital cosmetic surgery.
OBJECTIVES
The authors aim to propose a standard photographic scheme and physical examination form for the anatomical assessment of patients undergoing female genital surgery.
METHODS
The scheme containing 2 positions (standing and lithotomy positions) and 11 views (1 frontal and 2 oblique views from standing position; 6 frontal views with labia minora open and closed, pulled to the opposite side, clitoral hood pushed up, posterior fourchette stretched; 2 oblique views from lithotomy position) (2P11V) is applied to record pre- and postoperative appearance of the vulva. The evaluation form is utilized to record characteristics of different anatomical subunits during photography.
RESULTS
Two hundred forty-five patients who underwent female genital surgery were enrolled in the research from October 2018 to October 2022. All the patients received preoperative and postoperative 2P11V photography with about 5-minutes' shooting time. Various anatomical variations containing hypertrophy and prolapse of mons pubis, redundant types of labia minora and clitoral hood, incremental exposure of clitoral glans, hypo- to hypertrophy of labia majora, disappearance of interlabial groove, hypertrophy of posterior fourchette, and relation of subunits were accurately documented.
CONCLUSIONS
2P11V photographic scheme displays the isolated features of each organ and proportion relation among different parts of vulva. The standard photographic record and physical examination form offer detailed anatomical structure to surgeons and facilitate surgeons to carry out an accurate surgical design, which deserve to be promoted and applied.
Topics: Humans; Female; Genitalia, Female; Vulva; Clitoris; Hypertrophy; Photography
PubMed: 37140012
DOI: 10.1093/asj/sjad127