Hypnotic manipulation of effort sense during dynamic exercise: cardiovascular responses and brain activation

2001 ◽  
Vol 90 (4) ◽  
pp. 1392-1399 ◽  
Author(s):  
J. W. Williamson ◽  
R. McColl ◽  
D. Mathews ◽  
J. H. Mitchell ◽  
P. B. Raven ◽  
...  
Keyword(s):  
Perceived Exertion ◽  
Insular Cortex ◽  
Cardiovascular Responses ◽  
Constant Load ◽  
Dynamic Exercise ◽  
Anterior Cingulate ◽  
Regional Cerebral Blood ◽  
Ratings Of Perceived Exertion ◽  
Effort Sense ◽  
Constant Load Exercise

The purpose of this investigation was to hypnotically manipulate effort sense during dynamic exercise and determine whether cerebral cortical structures previously implicated in the central modulation of cardiovascular responses were activated. Six healthy volunteers (4 women, 2 men) screened for high hypnotizability were studied on 3 separate days during constant-load exercise under three hypnotic conditions involving cycling on a 1) perceived level grade, 2) perceived downhill grade, and 3) perceived uphill grade. Ratings of perceived exertion (RPE), heart rate (HR), blood pressure (BP), and regional cerebral blood flow (rCBF) distributions for several sites were compared across conditions using an analysis of variance. The suggestion of downhill cycling decreased both the RPE [from 13 ± 2 to 11 ± 2 (SD) units; P< 0.05] and rCBF in the left insular cortex and anterior cingulate cortex, but it did not alter exercise HR or BP responses. Perceived uphill cycling elicited significant increases in RPE (from 13 ± 2 to 14 ± 1 units), HR (+16 beats/min), mean BP (+7 mmHg), right insular activation (+7.7 ± 4%), and right thalamus activation (+9.2 ± 5%). There were no differences in rCBF for leg sensorimotor regions across conditions. These findings show that an increase in effort sense during constant-load exercise can activate both insular and thalamic regions and elevate cardiovascular responses but that decreases in effort sense do not reduce cardiovascular responses below the level required to sustain metabolic needs.

Brain activation by central command during actual and imagined handgrip under hypnosis

2002 ◽  
Vol 92 (3) ◽  
pp. 1317-1324 ◽  
Author(s):  
J. W. Williamson ◽  
R. McColl ◽  
D. Mathews ◽  
J. H. Mitchell ◽  
P. B. Raven ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Regional Cerebral Blood Flow ◽  
Perceived Exertion ◽  
Brain Activation ◽  
Cardiovascular Responses ◽  
Rating Of Perceived Exertion ◽  
Anterior Cingulate ◽  
Handgrip Exercise ◽  
Regional Cerebral Blood

The purpose was to compare patterns of brain activation during imagined handgrip exercise and identify cerebral cortical structures participating in “central” cardiovascular regulation. Subjects screened for hypnotizability, five with higher (HH) and four with lower hypnotizability (LH) scores, were tested under two conditions involving 3 min of 1) static handgrip exercise (HG) at 30% of maximal voluntary contraction (MVC) and 2) imagined HG (I-HG) at 30% MVC. Force (kg), forearm integrated electromyography, rating of perceived exertion, heart rate (HR), mean blood pressure (MBP), and differences in regional cerebral blood flow distributions were compared using an ANOVA. During HG, both groups showed similar increases in HR (+13 ± 5 beats/min) and MBP (+17 ± 3 mmHg) after 3 min. However, during I-HG, only the HH group showed increases in HR (+10 ± 2 beats/min; P < 0.05) and MBP (+12 ± 2 mmHg; P < 0.05). There were no significant increases or differences in force or integrated electromyographic activity between groups during I-HG. The rating of perceived exertion was significantly increased for the HH group during I-HG, but not for the LH group. In comparison of regional cerebral blood flow, the LH showed significantly lower activity in the anterior cingulate (−6 ± 2%) and insular cortexes (−9 ± 4%) during I-HG. These findings suggest that cardiovascular responses elicited during imagined exercise involve central activation of insular and anterior cingulate cortexes, independent of muscle afferent feedback; these structures appear to have key roles in the central modulation of cardiovascular responses.

Activation of the insular cortex is affected by the intensity of exercise

1999 ◽  
Vol 87 (3) ◽  
pp. 1213-1219 ◽  
Author(s):  
J. W. Williamson ◽  
R. McColl ◽  
D. Mathews ◽  
M. Ginsburg ◽  
J. H. Mitchell
Keyword(s):  
Perceived Exertion ◽  
Insular Cortex ◽  
Voluntary Contraction ◽  
Distribution Data ◽  
Regional Cerebral Blood ◽  
Ratings Of Perceived Exertion ◽  
Perceived Effort ◽  
Leg Cycling ◽  
Intensity Of Exercise ◽  
Cuff Occlusion

The purpose of this investigation was to determine whether there were differences in the magnitude of insular cortex activation across varying intensities of static and dynamic exercise. Eighteen healthy volunteers were studied: eight during two intensities of leg cycling and ten at different time periods during sustained static handgrip at 25% maximal voluntary contraction or postexercise cuff occlusion. Heart rate, blood pressure (BP), perceived exertion, and regional cerebral blood flow (rCBF) distribution data were collected. There were significantly greater increases in insular rCBF during lower (6.3 ± 1.7%; P < 0.05) and higher (13.3 ± 3.8%; P < 0.05) intensity cycling and across time during static handgrip (change from rest for right insula at 2–3 min, 3.8 ± 1.1%, P < 0.05; and at 4–5 min, 8.6 ± 2.8%, P < 0.05). Insular rCBF was decreased during postexercise cuff occlusion (−5.5 ± 1.2%; P < 0.05) with BP sustained at exercise levels. Right insular rCBF data, but not left, were significantly related, with individual BP changes ( r 2 = 0.80; P < 0.001) and with ratings of perceived exertion ( r 2 = 0.79; P < 0.01) during exercise. These results suggest that the magnitude of insular activation varies with the intensity of exercise, which may be further related to the level of perceived effort or central command.

The effect of antecedent fatiguing activity on the relationship between perceived exertion and physiological activity during a constant load exercise task

2007 ◽  
Vol 44 (5) ◽  
pp. 779-786 ◽  
Author(s):  
Roger Eston ◽  
James Faulkner ◽  
Alan St Clair Gibson ◽  
Tim Noakes ◽  
Gaynor Parfitt
Keyword(s):  
Perceived Exertion ◽  
Physiological Activity ◽  
Constant Load ◽  
The Relationship ◽  
Constant Load Exercise

scholarly journals Effects of surgical face masks on cardiopulmonary parameters during steady state exercise

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
J. Lässing ◽  
R. Falz ◽  
C. Pökel ◽  
S. Fikenzer ◽  
U. Laufs ◽  
...  
Keyword(s):  
Heart Rate ◽  
Steady State ◽  
Airway Resistance ◽  
Perceived Exertion ◽  
Endurance Performance ◽  
Constant Load ◽  
Rating Of Perceived Exertion ◽  
Lactate Minimum ◽  
Load Tests ◽  
Constant Load Exercise

AbstractWearing face masks reduce the maximum physical performance. Sports and occupational activities are often associated with submaximal constant intensities. This prospective crossover study examined the effects of medical face masks during constant-load exercise. Fourteen healthy men (age 25.7 ± 3.5 years; height 183.8 ± 8.4 cm; weight 83.6 ± 8.4 kg) performed a lactate minimum test and a body plethysmography with and without masks. They were randomly assigned to two constant load tests at maximal lactate steady state with and without masks. The cardiopulmonary and metabolic responses were monitored using impedance cardiography and ergo-spirometry. The airway resistance was two-fold higher with the surgical mask (SM) than without the mask (SM 0.58 ± 0.16 kPa l−1 vs. control [Co] 0.32 ± 0.08 kPa l−1; p < 0.01). The constant load tests with masks compared with those without masks resulted in a significantly different ventilation (77.1 ± 9.3 l min−1 vs. 82.4 ± 10.7 l min−1; p < 0.01), oxygen uptake (33.1 ± 5 ml min−1 kg−1 vs. 34.5 ± 6 ml min−1 kg−1; p = 0.04), and heart rate (160.1 ± 11.2 bpm vs. 154.5 ± 11.4 bpm; p < 0.01). The mean cardiac output tended to be higher with a mask (28.6 ± 3.9 l min−1 vs. 25.9 ± 4.0 l min−1; p = 0.06). Similar blood pressure (177.2 ± 17.6 mmHg vs. 172.3 ± 15.8 mmHg; p = 0.33), delta lactate (4.7 ± 1.5 mmol l−1 vs. 4.3 ± 1.5 mmol l−1; p = 0.15), and rating of perceived exertion (6.9 ± 1.1 vs. 6.6 ± 1.1; p = 0.16) were observed with and without masks. Surgical face masks increase airway resistance and heart rate during steady state exercise in healthy volunteers. The perceived exertion and endurance performance were unchanged. These results may improve the assessment of wearing face masks during work and physical training.

Perception of Effort during Constant Work to Self-Imposed Exhaustion

1979 ◽  
Vol 48 (3_suppl) ◽  
pp. 1111-1126 ◽  
Author(s):  
Donald H. Horstman ◽  
William P. Morgan ◽  
Allen Cymerman ◽  
James Stokes
Keyword(s):  
Perceived Exertion ◽  
Time To Exhaustion ◽  
Work Intensity ◽  
Ratings Of Perceived Exertion ◽  
Work Time ◽  
A Value ◽  
Perception Of Effort ◽  
Ventilatory Parameters ◽  
Effort Sense ◽  
High Work

The purpose of this study was to describe the pattern of change in effort sense and the value of this pattern in predicting work end-point at relatively high work intensity (80% V̇O2 max). The patterns of change of various physiological functions were also observed. Two modes of work (walking and running) were compared to ascertain generalizability of results. 26 healthy male volunteers served as subjects. Time to exhaustion (ET) did not differ between walking and running. As work continued during both tasks, significant increases of V̇E, V̇E/V̇O2, V̇E/V̇CO2 and HR and a significant decrease of ET were observed; while V̇O2 and R remained fairly constant. V̇O2 and V̇E during the run were about 5% greater than during the walk; there were no differences in other measures. Ratings of perceived exertion (RPE) from the Borg Scale were identical for both conditions, increasing in a near linear fashion from a value of 12.9 at 25% of total work time to 18.9 at exhaustion. Ratings obtained at 25 and 50% ET were extrapolated to time of exhaustion; the point of intercept corresponded to ratings of perceived exertion for maximal work. At exhaustion, subjects rated perception of respiratory exertion for the walk as less than that for the run; perception of leg exertion was not different for the two conditions. Plasma lactate, epinephrine and norepinephrine concentrations following exercise did not differ between the two conditions. The findings for the walking experiment were essentially replicated in a second investigation involving another 28 subjects. It is concluded that, with the exception of V̇O2 and some ventilatory parameters, walking and running ar the same relative work intensity resulted in comparable perceptual and physiological responses. Psychophysical judgments made early during work were reasonably accurate predictors of exhaustion time.

scholarly journals Constant Load Exercise at Gas Exchange Threshold is Accompanied by a Distinct Elevation in Blood Lactate Level

2020 ◽  
Author(s):  
kazuyuki kominami ◽  
Hirotaka Nishijima ◽  
Keiko Imahashi ◽  
Toko Katsuragawa ◽  
Mitsuyo Murakami ◽  
...  
Keyword(s):  
Steady State ◽  
Gas Exchange ◽  
Blood Lactate ◽  
Perceived Exertion ◽  
State Level ◽  
The Elderly ◽  
Constant Load ◽  
Healthy Elderly ◽  
Gas Exchange Threshold ◽  
Constant Load Exercise

Abstract Background: The gas exchange threshold (GET) is determined during incremental exercise (Inc-Ex) testing. It is generally considered to be a safe training intensity, with little or no elevation in blood lactate (BLa). However, actual exercise training at GET is carried out primarily as a constant load exercise (CL-Ex). The dynamics of BLa during CL-Ex at GET have not been studied. This study was conducted particularly among the elderly population. Methods: We recruited 20 healthy elderly individuals (H: age 69.4±6.8 years) and 10 patients with cardiovascular diseases or under medication for cardiovascular risk factors (P: age 73.0±8.8 years). On day 1, we determined GET during symptomatic maximal Inc-Ex. On day 2, CL-Ex at GET intensity was performed for 20 min. Arterialized blood lactate levels were determined. Results: The mean BLa at GET during Inc-Ex was 1.51±0.29 mmol/L in H and 1.78±0.42 mmol/L in P (p < 0.05). During CL-Ex, BLa increased significantly more than that at GET, reaching a steady state level of 2.65±1.56 (H) and 2.53±0.95 (P) mmol/L (ns), with a mean respiratory exchange ratio (RER) of 0.94±0.05 (H) and 0.93±0.05 (P) (ns). Oxygen uptake (VO2) also reached a steady state in all participants. All participants were able to complete CL-Ex with mean perceived exertion ratings (Borg/20) of 11.8±1.3 (H) and 12.2±1.3 (P) (ns). Conclusions: CL-Ex at GET occurred at distinctly increased BLa levels; however, BLa reached a steady state, together with VO2 and RER, indicating that exercise intensity was metabolically moderate.

The Effects of Creatine Supplementation on Cardiovascular, Metabolic, and Thermoregulatory Responses during Exercise in the Heat in Endurance-Trained Humans

2004 ◽  
Vol 14 (4) ◽  
pp. 443-460 ◽  
Author(s):  
L.P. Kilduff ◽  
E. Georgiades ◽  
N. James ◽  
R.H. Minnion ◽  
M. Mitchell ◽  
...  
Keyword(s):  
Prolonged Exercise ◽  
Sweat Rate ◽  
Creatine Supplementation ◽  
Cardiovascular Responses ◽  
Constant Load ◽  
Time To Exhaustion ◽  
Exercise Tests ◽  
Thermoregulatory Responses ◽  
Before And After ◽  
Constant Load Exercise

The effects of creatine (Cr) supplementation on cardiovascular, metabolic, and thermoregulatory responses, and on the capacity of trained humans to perform prolonged exercise in the heat was examined. Endurance-trained males (n = 21) performed 2 constant-load exercise tests to exhaustion at 63 ± 5 % VO2max in the heat (ambient temperature: 30.3 ± 0.5 °C) before and after 7 d of Cr (20 g · d–1 ’ Cr + 140 g • d–1 glucose polymer) or placebo. Cr increased intraccl-lular water and reduced thermoregulatory and cardiovascular responses (e.g., heart rate, rectal temperature, sweat rate) but did not significantly increase time to exhaustion (47.0 ± 4.7 min vs. 49.7 ± 7.5 min, P = 0.095). Time to exhaustion was increased significantly in subjects whose estimated intramuscular Cr levels were substantially increased (“responders”: 47.3 ± 4.9 min vs. 51.7 ± 7.4 min, P = 0.031). Cr-induced hyperhydration can result in a more efficient thermoregulatory response during prolonged exercise in the heat.

Evidence for central command activation of the human insular cortex during exercise

2003 ◽  
Vol 94 (5) ◽  
pp. 1726-1734 ◽  
Author(s):  
J. W. Williamson ◽  
R. McColl ◽  
D. Mathews
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Perceived Exertion ◽  
Insular Cortex ◽  
Emission Computed Tomography ◽  
Central Command ◽  
Handgrip Exercise ◽  
Ratings Of Perceived Exertion ◽  
Blood Pressure Elevation ◽  
Cuff Occlusion

The purpose of this investigation was to determine whether central command activated regions of the insular cortex, independent of muscle metaboreflex activation and blood pressure elevations. Subjects ( n = 8) were studied during 1) rest with cuff occlusion, 2) static handgrip exercise (SHG) sufficient to increase mean blood pressure (MBP) by 15 mmHg, and 3) post-SHG exercise cuff occlusion (PECO) to sustain the 15-mmHg blood pressure increase. Data were collected for heart rate, MBP, ratings of perceived exertion and discomfort, and regional cerebral blood flow (rCBF) by using single-photon-emission computed tomography. When time periods were compared when MBP was matched during SHG and PECO, heart rate (7 ± 3 beats/min; P < 0.05) and ratings of perceived exertion (15 ± 2 units; P < 0.05) were higher for SHG. During SHG, there were significant increases in rCBF for hand sensorimotor (9 ± 3%), right inferior posterior insula (7 ± 3%), left inferior anterior insula (8 ± 2%), and anterior cingluate regions (6 ± 2%), not found during PECO. There was significant activation of the inferior (ventral) thalamus and right inferior anterior insular for both SHG and PECO. Although prior studies have shown that regions of the insular cortex can be activated independent of mechanoreflex input, it was not presently assessed. These findings provide evidence that there are rCBF changes within regions of the insular and anterior cingulate cortexes related to central command per se during handgrip exercise, independent of metaboreflex activation and blood pressure elevation.

High Carbohydrate Diet Induces Faster Final Sprint and Overall 10,000-m Times of Young Runners

2015 ◽  
Vol 27 (3) ◽  
pp. 355-363 ◽  
Author(s):  
Patricia Guimaraes Couto ◽  
Romulo Bertuzzi ◽  
Carla Caroline de Souza ◽  
Hessel Marani Lima ◽  
Maria Augusta Peduti Dal Molin Kiss ◽  
...  
Keyword(s):  
Perceived Exertion ◽  
Constant Load ◽  
Rating Of Perceived Exertion ◽  
Carbohydrate Diet ◽  
Dietary Regimen ◽  
Oxidation Rates ◽  
High Carbohydrate ◽  
Performance Time ◽  
And Performance ◽  
Constant Load Exercise

This study analyzed the pacing employed by young runners in 10,000 m time-trials under 3 dietary regimens of different carbohydrate (CHO) intakes. Nineteen boys (13–18 years) ate either their normal CHO diet (56% CHO), high (70% CHO), or low (25% CHO) CHO diets for 48 hr; the boys then performed a 10,000 m run (crossover design). The high CHO diet led to faster final sprint (14.4 ± 2.2 km·h-1) and a better performance (50.0 ± 7.0 min) compared with the low CHO diet (13.3 ± 2.4 km·h-1 and 51.9 ± 8.3 min, respectively, p < .05). However, the final sprint and performance time in the high CHO or low CHO diets were statistically not significantly different from the normal CHO diet (13.8 ± 2.2 km·h-1 and 50.9 ± 7.4 min; p > .05). CHO oxidation rate during the constant load exercise at 65% of VO2max was elevated in high CHO diet (1.05 ± 0.38 g·min-1) compared with low CHO diet (0.63 ± 0.36 g·min-1). The rating of perceived exertion increased linearly throughout the trial, independently of the dietary regimen. In conclusion, the high CHO diet induced higher CHO oxidation rates, increased running speed in the final 400 m and enhanced overall running performance, compared with low CHO.

Sign in / Sign up

Export Citation Format

Share Document