142 research outputs found
For arts' sake?: Contemporary dance in South Africa
Abstract
Gregory Maqoma, a leading South African contemporary choreographer, mixes elements
to create work that is unpredictable and difficult to pin down. His hybrid form of dance
contradicts essentialised representations of post-apartheid South Africa. Using layered
ethnographic analysis, this thesis examines his work in order to discuss the conversation
between art and society in a country that is forming a new democracy. Through the
questions that his work raises, this research explores what it means to be âAfricanâ, the
problems of authenticity, processes of signification and its relationship to embodiment,
and the place of the performing arts in the ânewâ South African context. It illustrates the
potency of art as social commentary, and asserts that freedom and its limits cannot be
critically evaluated without considering the dialogue offered by contemporary artistic
performance
The effect of environmental conditions on the physiological response during a stand-up paddle surfing session
Stand Up Paddleboard (SUP) surfing entails riding breaking waves and maneuvering the board on the wave face in a similar manner to traditional surfing. Despite some scientific investigations on SUP, little is known about SUP surfing. The aim of this study was to investigate the physiological response during SUP surfing sessions and to determine how various environmental conditions can influence this response. Heart rate (HR) of an experienced male SUP surfer aged 43 was recorded for 14.9 h during ten surfing sessions and synced with on board video footage to enable the examination of the effect of different surfing modes and weather conditions on exercise intensity. Results indicated that the SUP surferâs HR was above 70% of HRmax during 85% of each session, with the greatest heart rates found during falls off the board (~85% HRmax) and while paddling back to the peak (~83% HRmax). Total time surfing a wave was less than 5%, with the majority of time spent paddling back into position. Wind speed positively correlated with HR (r = 0.75, p < 0.05) and wave height negatively correlated with wave caching frequency (r = 0.73, p < 0.05). The results highlight the aerobic fitness for SUP surfing, where wave riding, paddling back to the peak, and falls appear to be associated with the greatest cardiovascular demand and demonstrate that environmental conditions can have an effect on the physiological response during SUP surfing sessions
Characterizing Movement Patterns of Older Individuals with T2D in Free-Living Environments Using Wearable Accelerometers
(1) Background: Type 2 Diabetes (T2D) is associated with reduced muscle mass, strength, and function, leading to frailty. This study aims to analyze the movement patterns (MPs) of older individuals with T2D across varying levels of physical capacity (PC). (2) Methods: A cross-sectional study was conducted among individuals aged 60 or older with T2D. Participants (n = 103) were equipped with a blinded continuous glucose monitoring (CGM) system and an activity monitoring device for one week. PC tests were performed at the beginning and end of the week, and participants were categorized into three groups: low PC (LPC), medium PC (MPC), and normal PC (NPC). Group differences in MPs and physical activity were analyzed using non-parametric Kruskal-Wallis tests for both categorical and continuous variables. Dunn post-hoc statistical tests were subsequently carried out for pairwise comparisons. For data analysis, we utilized pandas, a Python-based data analysis tool, and conducted the statistical analyses using the scipy.stats package in Python. The significance level was set at p < 0.05. (3) Results: Participants in the LPC group showed lower medio-lateral acceleration and higher vertical and antero-posterior acceleration compared to the NPC group. LPC participants also had higher root mean square values (1.017 m/s2). Moreover, the LPC group spent less time performing in moderate to vigorous physical activity (MVPA) and had fewer daily steps than the MPC and NPC groups. (4) Conclusions: The LPC group exhibited distinct movement patterns and lower activity levels compared to the NPC group. This study is the first to characterize the MPs of older individuals with T2D in their free-living environment. Several accelerometer-derived features were identified that could differentiate between PC groups. This novel approach offers a manpower-free alternative to identify physical deterioration and detect low PC in individuals with T2D based on real free-living physical behavior
Exercise Increases Pressure Pain Tolerance but Not Pressure and Heat Pain Thresholds in Healthy Young Men
Background: Exercise causes an acute decrease in the pain sensitivity known as exercise-induced hypoalgesia (EIH), but the specificity to certain pain modalities remains unknown. This study aimed to compare the effect of isometric exercise on the heat and pressure pain sensitivity.
Methods: On three different days, 20 healthy young men performed two submaximal isometric knee extensions (30% maximal voluntary contraction in 3 min) and a control condition (quiet rest). Before and immediately after exercise and rest, the sensitivity to heat pain and pressure pain was assessed in randomized and counterbalanced order. Cuff pressure pain threshold (cPPT) and pain tolerance (cPTT) were assessed on the ipsilateral lower leg by computer-controlled cuff algometry. Heat pain threshold (HPT) was recorded on the ipsilateral foot by a computer-controlled thermal stimulator.
Results: Cuff pressure pain tolerance was significantly increased after exercise compared with baseline and rest (p \u3c 0.05). Compared with rest, cPPT and HPT were not significantly increased by exercise. No significant correlation between exercise-induced changes in HPT and cPPT was found. Testâretest reliability before and after the rest condition was better for cPPT and CPTT (intraclass correlation \u3e 0.77) compared with HPT (intraclass correlation = 0.54).
Conclusions: The results indicate that hypoalgesia after submaximal isometric exercise is primarily affecting tolerance of pressure pain compared with the pain threshold. These data contribute to the understanding of how isometric exercise influences pain perception, which is necessary to optimize the clinical utility of exercise in management of chronic pain.
Significance: The effect of isometric exercise on pain tolerance may be relevant for patients in chronic musculoskeletal pain as a pain-coping strategy.
What does this study add? The results indicate that hypoalgesia after submaximal isometric exercise is primarily affecting tolerance of pressure pain compared with the heat and pressure pain threshold. These data contribute to the understanding of how isometric exercise influences pain perception, which is necessary to optimize the clinical utility of exercise in management of chronic pain
Interactive cervical motion kinematics: sensitivity, specificity and clinically significant values for identifying kinematic impairments in patients with chronic neck pain
Chronic neck pain has been consistently shown to be associated with impaired kinematic control including reduced range, velocity and smoothness of cervical motion, that seem relevant to daily function as in quick neck motion in response to surrounding stimuli. The objectives of this study were: to compare interactive cervical kinematics in patients with neck pain and controls; to explore the new measures of cervical motion accuracy; and to find the sensitivity, specificity, and optimal cutoff values for defining impaired kinematics in those with neck pain. In this cross-section study, 33 patients with chronic neck pain and 22 asymptomatic controls were assessed for their cervical kinematic control using interactive virtual reality hardware and customized software utilizing a head mounted display with built-in head tracking. Outcome measures included peak and mean velocity, smoothness (represented by number of velocity peaks (NVP)), symmetry (represented by time to peak velocity percentage (TTPP)), and accuracy of cervical motion. Results demonstrated significant and strong effect-size differences in peak and mean velocities, NVP and TTPP in all directions excluding TTPP in left rotation, and good effect-size group differences in 5/8 accuracy measures. Regression results emphasized the high clinical value of neck motion velocity, with very high sensitivity and specificity (85%â100%), followed by motion smoothness, symmetry and accuracy. These finding suggest cervical kinematics should be evaluated clinically, and screened by the provided cut off values for identification of relevant impairments in those with neck pain. Such identification of presence or absence of kinematic impairments may direct treatment strategies and additional evaluation when needed
Effect of permissive dehydration on induction and decay of heat acclimation, and temperate exercise performance
Purpose: It has been suggested that dehydration is an independent stimulus for heat
32 acclimation (HA), possibly through influencing fluid-regulation mechanisms and increasing
33 plasma volume (PV) expansion. There is also some evidence that HA may be ergogenic in
34 temperate conditions and that this may be linked to PV expansion. We investigated: i) the
35 influence of dehydration on the time-course of acquisition and decay of HA; ii) whether
36 dehydration augmented any ergogenic benefits in temperate conditions, particularly those
related to PV expansion. Methods: Eight males (VO2max: 56.9(7.2) mL·kg-1
·min-1
37 ) undertook
38 two HA programmes (balanced cross-over design), once drinking to maintain euhydration
39 (HAEu) and once with restricted fluid-intake (HADe). Days 1, 6, 11 and 18 were 60 min exercise-
40 heat stress tests (HST [40°C; 50%RH]), days 2-5 and 7-10 were 90 min, isothermal-strain
41 (Tre~38.5°C), exercise-heat sessions. Performance parameters (VO2max, lactate threshold,
42 efficiency, peak power output [PPO]) were determined pre and post HA by graded exercise test
43 (22°C; 55 %RH). Results: During isothermal-strain sessions hypohydration was achieved in
44 HADe and euhydration maintained in HAEu (average body mass loss -2.71(0.82)% vs. -
45 0.56(0.73)%, P<0.001), but aldosterone concentration, power output and cardiovascular strain
46 were unaffected by dehydration. HA was evident on day 6 (reduced end-exercise Tre [-
0.30°C(0.27)] and exercise heart rate [-12(15) beats.min-1
47 ], increased PV [+7.2(6.4)%] and
sweat-loss [+0.25(0.22) L.hr-1
48 ], P<0.05) with some further adaptations on day 11 (further
reduced end-exercise Tre [-0.25(0.19)°C] and exercise heart rate [-3(9) beats.min-1
49 ], P<0.05).
50 These adaptations were not notably affected by dehydration and were generally maintained 7-
51 days post HA. Performance parameters were unchanged, apart from increased PPO (+16(20)
52 W, irrespective of condition). Conclusions: When thermal-strain is matched, permissive
53 dehydration which induces a mild, transient, hypohydration does not affect the acquisition and
54 decay of HA, or endurance performance parameters. Irrespective of hydration, trained
55 individuals require >5 days to optimise HA
Forging networks and mixing ores: rethinking the social landscapes of iron metallurgy
This research explores the networks of technological knowledge that influenced changes in the iron production
practices of western Uganda in the second half of the second millennium AD. Temporal and spatial variability in
technological processes were observed within the research area, in terms of the style and construction of the
furnaces, the use of a manganese-rich flux, and the configuration of tuyĂšres. These shifts were considered in
relation to the social dimensions of iron production, specifically the protection of technical knowledge. Informed
by ethnographic data from the study area, variations were noted in the participation in, or exclusion from, iron
production activity on the basis of gender and clan affiliation. This stands in contrast to ethno-historic accounts
that speak of a strongly regulated production environment.
This paper considers that an uncritical emphasis on conservatism provides an inadequate framework for
addressing long-term change in iron production technologies. It suggests that constellations of knowledge in
western Uganda fostered the potential for innovation and experimentation, resulting in dynamic technological
practice. This paper urges a more nuanced discussion of how complex metallurgical technologies transform and
move within cultural and physical landscapes, with ramifications for how we conceptualize the emergence and
adoption of early technologies
Effect of shortâterm heat acclimation with permissive dehydration on thermoregulation and temperate exercise performance
We examined the effect of short-term heat acclimation with permissive dehydration (STHADe) on heat acclimation (HA) and cycling performance in a temperate environment. Ten trained male cyclists (Mean(SD) maximal oxygen uptake: 63.3(4.0)mL·kg-1·min-1; peak power output [PPO]: 385(40)W; training: 10(3)hours·week-1) underwent a STHADe programme consisting of five-days of exercise (maximum 90mins·day-1) in a hot environment (40°C, 50%RH) to elicit isothermic heat strain (rectal temperature 38.64(0.27)°C). Participants abstained from fluids during, and 30-minutes after, HA sessions. Pre- and post-STHADe HA was evaluated during euhydrated fixed-intensity exercise (60mins) in hot conditions; the effect of STHADe on thermoregulation was also examined under temperate conditions (20mins fixed-intensity exercise; 22°C, 60%RH). Temperate cycling performance was assessed by a graded exercise test (GXT) and 20-km time trial (TT). STHADe reduced thermal and cardiovascular strain in hot and temperate environments. Lactate threshold (Î=16(17)W) and GXT PPO (Î=6(7)W) were improved following STHADe (P0.05), although there was a trend for a higher mean power (P=0.06). In conclusion, STHADE can reduce thermal and cardiovascular strain under hot and temperate conditions and there is some evidence of ergogenic potential for temperate exercise, but longer HA regimens may be necessary for this to meaningfully influence performance
Differential pain response at local and remote muscle sites following aerobic cycling exercise at mild and moderate intensity
Physical exercise has been shown to inhibit experimental pain response in the post-exercise period. Modulation of the pain system may be differentiated between muscle sites engaging in contractile activity. The purpose of this study was to assess the pain response at remote and local muscle sites following aerobic exercise at different work intensities. Participants included 10 healthy and physically active males (mean age ± SD, 21.2 ± 3.4). Somatic pressure pain threshold (PPT) at the rectus femoris (local) and brachioradialis (remote) muscle site was measured at before (Pre), 5 min after (Post1), and 15 min after (Post2) aerobic cycling exercise at 70 and 30 % of peak oxygen uptake (VO(2peak)) performed on different occasions in a counterbalanced order, separated by minimum of 3 days interval. Repeated measures ANOVA for PPT reveals significant main effect for time (f = 3.581, p = 0.049, observed power = 0.588) and muscle site (f = 17.931, p = 0.002, observed power = 0.963). There was a significant interaction shown for exercise intensity by time (f = 11.390, p = 0.012, observed power = 0.790). PPT at rectus femoris following cycling exercise at 70 % of VO(2peak) reveals a significant increase between Pre-Post1 (p = 0.040). PPT for rectus femoris following cycling exercise at 30 % of VO(2peak) revealed a significant decrease between Pre-Post1 (p = 0.026) and Pre-Post2 (p = 0.008). The PPT for brachioradialis following cycling exercise at 30 % of VO(2peak) revealed a significant decrease between Pre-Post1 (p = 0.011) and Pre-Post2 (p = 0.005). These results show that aerobic exercise increases PPT locally at the exercise muscle site following exercise at 70 % of VO(2peak) but reduces PPT following exercise at 30 % of VO(2peak)
Life (and limb) in the fast-lane:Disposable people as infrastructure in Kampalaâs boda boda industry
Motorcycle taxis, dubbed boda bodas, constitute a vital aspect of Kampalaâs transportation infrastructure, yet the industry is perpetually precarious, threatened with wholesale eviction. Moreover, driversâ lives and bodies are continually put at risk by the cityâs traffic. Through a relational approach to ontology, this article asks how the boda boda industry comes into being and endures, what forms of vulnerability it entails, and what experiences, relations, and forms of urban life it produces. It argues that three forms disposability structure and arise from the industry â structural unemployment, embodied vulnerability, and infrastructural displacement. Infrastructural violence, it is argued, must be considered when describing and theorizing people as infrastructure. The article examines how boda boda driversâ shared condition of insecurity and disposability generates intense forms of sociality, solidarity, mutual obligation, recognition, and urban vitality
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