‘Weather work’: embodiment and weather learning in a national outdoor exercise programme

Over the past 25 years, UK government policy exhortations to promote and increase exercise and physical activity levels in the population have increased in volume. In recent years, too, there has been growing sociological interest in exercise and physical activity embodiment issues, including within phenomenologically-inspired research into lived-body experiences. This article contributes original insights to a developing body of phenomenological-sociological empirical work in this domain, in addressing the lived experience of organised exercise in outdoor environments, and specifically in theorising the role of ‘lived weather’ in contouring these experiences. It thus addresses the call by Vannini et al. (2012) to remedy the notable ‘absent-presence’ of weather in much social science research. Drawing upon data from a two-year multi-disciplinary, multi-institutional ethnographic study of a nationwide exercise programme in Wales, UK, this article examines participants’ (n = 146) lived experience of weather, and theorises their ‘weather learning’, and ‘weather work’, both of which emerged as highly salient in the findings

Postprandial lipemia: effects of intermittent versus continuous exercise

PURPOSE: The purpose of this study was to assess whether exercise performed in continuous and discontinuous formats reduced postprandial lipemia to a similar degree.<p></p> METHODS: Fifteen normolipidemic and three borderline hyperlipidemic healthy males (ages 30.6 +/- 9.0 (mean +/- SD) yr, BMI 23.1 +/- 1.4 kg.m-2) participated in three trials, each conducted over 2 d. Subjects refrained from exercise for the 2 d preceding each trial. On day one, subjects rested (control trial), or ran at 60% of maximal oxygen uptake in either one 90-min session (continuous exercise trial), or three 30-min sessions (intermittent exercise trial). On day two, subjects ingested a high-fat test breakfast (1.2 g fat, 1.2 g carbohydrate, 70 kJ energy per kilogram body mass). Blood samples were obtained in the fasted state and at intervals for 6 h postprandially.<p></p> RESULTS: Fasting plasma triacylglycerol (TAG) concentrations did not differ between trials. Areas under the TAG versus time curves were 18.1 +/- 6.7% (mean +/- SEM) and 17.7 +/- 7.6% (both P 0.05) lower than control in the continuous exercise and intermittent exercise trials, respectively. Plasma glucose responses to the test meal did not differ between trials, but the serum insulin response was lower in the intermittent exercise trial compared with that in the control.<p></p> CONCLUSION: The results suggest that both intermittent and continuous exercise can reduce postprandial lipemia.<p></p&gt

Are the reductions in triacylglycerol and insulin levels after exercise related?

Moderate exercise improves insulin sensitivity and reduces triacylglycerol (triglyceride; TG) concentrations. We hypothesized that changes in insulin sensitivity are an important determinant of exercise-induced changes in postprandial TG concentrations. Altogether, 38 men and 43 women, all of whom were normotriglyceridaemic and normoglycaemic, each underwent two oral fat tolerance tests with different pre-conditions: control (no exercise) and prior exercise (90min of exercise at 60% of maximal O2 uptake the day before). Venous blood samples were obtained in the fasting state and for 6h after a high-fat mixed meal. In the control trial there were significant correlations between log fasting TG concentration and log fasting insulin concentration (r = 0.42, P < 0.0005) and between log postprandial TG response (area under the curve) and log postprandial insulin response (r = 0.48, P < 0.0005). Prior exercise reduced the fasting TG concentration by 18.2±2.2% (mean±S.E.M.) (P < 0.0005), the postprandial TG response by 21.5±1.9% (P < 0.0005), the fasting insulin concentration by 3.8±3.1% (P < 0.01) and the postprandial insulin response by 11.9±2.5% (P < 0.0005). However, there was no relationship between the exercise-induced changes in log fasting TG and log fasting insulin (r = 0.08, P = 0.50), nor between the exercise-induced changes in log postprandial TG response and log postprandial insulin response (r = 0.04, P = 0.70). These data suggest that the reductions in fasting and postprandial TG levels elicited by a session of moderate-intensity exercise are not mediated by an increase in insulin sensitivity

The reduction in postprandial lipemia after exercise is independent of the relative contributions of fat and carbohydrate to energy metabolism during exercise

A single session of exercise several hours before a high-fat meal reduces postprandial lipemia. The purpose of the present study was to test the hypothesis that this effect is independent of substrate metabolism during exercise. Twelve men aged 21 to 36 years underwent three oral fat tolerance tests with intervals of at least 1 week. On one occasion, only activities of daily living were allowed the preceding day (control). On the other two occasions, subjects ran on a treadmill for 90 minutes on the afternoon preceding the fat tolerance test; 90 minutes before running, they ingested either acipimox, an inhibitor of lipolysis in adipose tissue, or placebo. Acipimox abolished the increase in the nonesterified fatty acid (NEFA) concentration observed during the run after placebo and reduced lipid oxidation (placebo, 37 ± 7 g; acipimox, 21 ± 3 g; P < .05, mean ± SEM), but had no effect on gross energy expenditure (placebo, 4.86 ± 0.20 MJ; acipimox, 4.83 ± 0.18 MJ). Before each of the three fat tolerance tests, subjects reported to the laboratory after an overnight fast. Blood samples were obtained in the fasted state and for 6 hours after consumption of a high-fat meal (per kilogram of body mass: 1.2 g fat, 1.2 g carbohydrate, and 61 kJ energy). Plasma concentrations of NEFA were higher postprandially with acipimox, compared with control and placebo (P < .05), as were glucose concentrations measured over the first 5 hours. The insulin response to the meal was lower in placebo compared with control and acipimox (P < .05). Despite these counterregulatory responses, postprandial lipemia was reduced to the same degree (compared with control, P < .05) by exercise preceded by acipimox and by exercise preceded by placebo (area under the plasma triacylglycerol concentration v time curve: control, 8.77 ± 1.17 mmol/L · 6 h; placebo, 6.95 ± 0.97 mmol/L · 6 h; acipimox, 6.81 ± 0.81 mmol/L · 6 h). These findings suggest that some factor other than the nature of the metabolic substrate used during exercise determines the attenuating effect of prior exercise on postprandial lipemia

Effects of a brisk walk on lipoprotein lipase activity and plasma triglyceride concentrations in the fasted and postprandial states

This study aimed to determine whether changes in plasma heparin-releasable lipoprotein lipase (LPL) activity following a brisk walk were associated with decreases in fasting and/or postprandial triglyceride (TG) concentrations. Two groups of pre-menopausal women participated. In one group (fasting study group, n=10), TG concentrations and post-heparin plasma LPL activity were measured in the fasted state on two occasions: ~18 h after a 2-h treadmill walk at 50% maximal oxygen uptake (exercise trial); and after a day of no exercise (control trial). The other group (postprandial study group, n=9) undertook two oral fat tolerance tests (blood samples taken fasting and for 6 h after a high-fat meal), with plasma LPL activity measured 6 h after meal ingestion. Pre-conditions were the same as for the fasting study group (i.e. control and prior exercise). Prior exercise reduced fasting TG concentrations by 23 (7)% (fasting study group) [mean (SEM)] and by 18 (9)% (postprandial study group) (both P<0.05), and the postprandial TG response by 23 (6)% (postprandial study group) (P<0.01). Plasma LPL activity was not significantly increased by exercise in either the fasting or postprandial study groups. However, exercise-induced changes in both fasting and postprandial LPL activity were significantly correlated with the respective exercise-induced changes in fasting TG concentration and the postprandial TG response (r=−0.70 and −0.77 respectively, P<0.05 for both). These data suggest that increased LPL activity may contribute to the hypotriglyceridaemic effect of moderate exercise, although other mechanisms are also likely to be involved

Accumulating brisk walking for fitness, cardiovascular risk and psychological health

MURPHY, M., A. NEVILL, C. NEVILLE, S. BIDDLE, and A. HARDMAN. Accumulating brisk walking for fitness, cardiovascular risk, and psychological health. Med. Sci. Sports Exerc., Vol. 34, No. 9, pp. 1468–1474, 2002. Purpose: To compare the effects of different patterns of regular brisk walking on fitness, risk factors for cardiovascular disease, and psychological well-being in previously sedentary adults. Methods: Twenty-one subjects (14 women), aged 44.5 ± 6.1 yr (mean ± SD) were randomly assigned to two different, 6-wk programs of brisk walking in a cross-over design, with an interval of 2 wk. One program comprised one 30-min walk per day, 5 d·wk-1 (long bout) and the other three 10-min walks per day, also 5 d·wk-1 (short bouts). All walking was at 70–80% of predicted maximal heart rate. Maximal oxygen uptake ([latin capital V with dot above]O2max), body composition, resting arterial blood pressure, fasting plasma lipoprotein variables, and psychological parameters were assessed before and after each program. Results: Overall, subjects completed 88.2 ± 1.1% and 91.3 ± 4.1% of prescribed total walking time in the short- and long-bout programs, respectively. Both programs increased plasma concentrations of high-density lipoprotein cholesterol, and decreased concentrations of triacylglycerol and total cholesterol (all P < 0.05). There were no changes in body mass, but the sum of four skinfolds, waist circumference, and hip circumference were decreased after both walking programs (all P < 0.05). Predicted [latin capital V with dot above]O2max increased with both programs (P < 0.05), but this increase was greater with the program based on short bouts (P < 0.05). Both walking patterns resulted in similar decreases in tension/anxiety (P < 0.05). Conclusion: These findings suggest that three short bouts (10 min) of brisk walking accumulated throughout the day are at least as effective as one continuous bout of equal total duration in reducing cardiovascular risk and improving aspects of mood in previously sedentary individuals

The nature and age of Mesoproterozoic strike-slip faulting based on Re-Os geochronology of syn-tectonic copper mineralization, Assynt Terrane, NW Scotland

In ancient basement regions such as the Lewisian Complex, NW Scotland, the ages of brittle deformation events are commonly poorly constrained due to a lack of datable fills. An array of NW-SE sinistral and antithetic E-W dextral faults related to a regionally recognized episode of brittle shearing cut Neoarchaean gneisses and c. 2.25 Ga quartz-pyrite veins close to the trace of the unexposed, regional-scale NW-SE fault. Copper-iron mineralisation occurs at an intersection between an antithetic dextral fault and an older c. 2.25 Ga quartz vein. Optical microscopy, SEM and XRD analyses reveal an array of intergrown, co-genetic copper-iron sulphides, hematite and barite. Complex mm-thick zoned alteration rims rich in epidote occur at contacts between the sulphides and gneisses. Rhenium-Osmium copper-iron sulphide geochronology yields an age of c. 1.55 Ga for the hydrothermal mineralization event associated with faulting. Fault movements demonstrably overlap with mineralisation based on the asymmetric fibrous growth forms of these minerals within local dextral shears which acted as local channelways for mineralizing fluids during and after faulting. We tentatively propose that this regionally recognised strike slip faulting, previously termed the ‘Late Laxfordian’, should be referred to as the ‘Assyntian’ in order to distinguish it from kinematically distinct Laxfordian events