Perceptual Responses Research Articles

Acute Physiological and Perceptual Responses to Whole-Body High-Intensity Interval Training Compared with Equipment-Based Interval and Continuous Training

Low-volume, time-efficient high-intensity interval training (HIIT), which involves whole-body (WB) callisthenics exercises, has gained worldwide popularity in recent years. However, the physiological and perceptual impact of WB-HIIT in comparison to specialised, equipment-based training is relatively less studied. This study compared the acute physiological and perceptual responses to a single session of WB-HIIT, ergometer-based HIIT (ERG-HIIT) and conventional moderate-intensity continuous training (MICT). Fourteen physically inactive adults (age: 28.4 ± 6.5 years, VO2peak: 31.0 ± 6.2 mL· kg-1· min-1) underwent three main trials (WB-HIIT: 12 x 30-s high-intensity callisthenics workout; ERG: HIIT: 12 x 30-s high-intensity cycling bouts; MICT: 30-min cycling at 50% peak power output) in a randomized cross-over order 3-7 days apart. The mean session heart rate (HR) and perceived exertion were comparable across all three protocols (p > 0.05). WB-HIIT attained a similar peak HR (87.4 ± 9.4 %HRmax) as that of ERG-HIIT (83.0 ± 8.6 %HRmax), and significantly greater than that of MICT (78.7 ± 5.5 %HRmax, p = 0.001). However, WB-HIIT induced significantly higher blood lactate levels (7.2 ± 1.8 mmol/L) compared to both ERG-HIIT (5.1 ± 1.3 mmol/L, p < 0.05) and MICT (3.1 ± 1.5 mmol/L, p < 0.001). The participants reported higher self-efficacy and greater enjoyment with WB-HIIT compared to MICT (p < 0.05). The mean HR and perceived exertion responses to WB-HIIT are comparable to those of equipment-based HIIT and MICT; however, WB-HIIT results in greater metabolic strain than both other modalities. Despite this, the overall perceptual responses to WB-HIIT are positive, suggesting that it could be a viable exercise alternative, especially for individuals with limited exercise time and restricted access to facilities and equipment.

Children's Physiological and Perceptual Responses to Sports Exergames When Played in Different Positions.

Today's children are prone to becoming involved in exergames, but their positions during play have not been sufficiently investigated to determine whether the positions they adopt result in equal responses. The design of this study involved the collection of physiological and perceptual responses (i.e., heart rate (HR), rating of perceived exertion, and enjoyment score) during exergames in three different sports (bowling, tennis, and boxing) with players in different positions (sitting and standing). The participants played each game for 10 min while their HR was recorded. After the gameplay, each perceptual response was retrieved. The results revealed a significant increase in HR above rest during exergaming overall (p < 0.001). Standing gameplay resulted in a significantly higher HR (p < 0.001) than seated gameplay. Compared to tennis and bowling, boxing produced the highest physiological response (p < 0.001) and perceived exertion (p < 0.05) in both positions. The participants perceived all the sports exergames to be enjoyable, as their enjoyment scores did not significantly differ for each game (p > 0.5). For all the variables, no statistically significant differences between genders were identified (p > 0.5). This home-based intervention demonstrated that sports exergames are not only enjoyable; overall, they can provide at least moderately intense physical activity, whether played seated or standing.

Reduced running performance and greater perceived exertion, but similar post-exercise neuromuscular fatigue in tropical natives subjected to a 10 km self-paced run in a hot compared to a temperate environment.

Environmental heat stress impairs endurance performance by enhancing exercise-induced physiological and perceptual responses. However, the time course of these responses during self-paced running, particularly when comparing hot and temperate conditions, still needs further clarification. Moreover, monitoring fatigue induced by exercise is paramount to prescribing training and recovery adequately, but investigations on the effects of a hot environment on post-exercise neuromuscular fatigue are scarce. This study compared the time course of physiological and perceptual responses during a 10 km self-paced treadmill run (as fast as possible) between temperate (25°C) and hot (35°C) conditions. We also investigated the changes in countermovement jump (CMJ) performance following exercise in these two ambient temperatures. Thirteen recreational long-distance runners (11 men and 2 women), inhabitants of a tropical region, completed the two experimental trials in a randomized order. Compared to 25°C, participants had transiently higher body core temperature (TCORE) and consistently greater perceived exertion while running at 35°C (p < 0.05). These changes were associated with a slower pace, evidenced by an additional 14 ± 5 min (mean ± SD) to complete the 10 km at 35°C than at 25°C (p < 0.05). Before, immediately after, and 1 h after the self-paced run, the participants performed CMJs to evaluate lower limb neuromuscular fatigue. CMJ height was reduced by 7.0% (2.3 ± 2.4 cm) at 1 h after the race (p < 0.05) compared to pre-exercise values; environmental conditions did not influence this reduction. In conclusion, despite the reduced endurance performance, higher perceived exertion, and transiently augmented TCORE caused by environmental heat stress, post-exercise neuromuscular fatigue is similar between temperate and hot conditions. This finding suggests that the higher external load (faster speed) at 25°C compensates for the effects of more significant perceptual responses at 35°C in inducing neuromuscular fatigue.

Repeated High-Intensity Technique Training and Repeated Sprint Training Elicit Similar Adjustment in Physiological Responses But Divergent Perceptual Responses and Combat-Related Performances in Adolescent Taekwondo Matches.

This study investigated the effects of 4 weeks of repeated sprint training (RST) versus repeated high-intensity technique training (RTT) on the physiological responses (ie,blood lactate), mean and peak heart rate, rating of perceived exertion, technical-tactical performance, and time-motion variables during simulated taekwondo combats. Twenty-four taekwondo athletes (18 male and 6 female; age: 16 [1]y) were randomly and equally assigned to RST (10 × 35-m running sprints interspersed by 10-s rest) or RTT (10 × 6-s bandal-tchagui kicking executions interspersed by 10-s rest) groups in addition to their regular training. Both groups performed simulated combats before and after training. Delta lactate and peak heart rate were attenuated following training (P < .001 and P = .03, respectively), with no differences identified between RTT and RST conditions. Rating of perceived exertion decreased after training only in the RTT (P = .002). Time fighting and preparatory activities increased following training (P < .001), with higher values observed following RTT than RST (P < .001). Nonpreparatory time decreased after training (P < .001), with more pronounced reductions observed following RTT when compared to RST (P < .001). The number of single attacks decreased only following RST (P < .001), whereas combined attacks increased only after RTT training (P < .001). Similar adjustments in the physiological responses to combat were observed following 4 weeks of either RST or RTT, but RTT elicited more favorable perceptual responses and combat-related performance. This highlights the importance of specificity of training and its effective transfer to combat.

Exercise responses to heart rate clamped cycling with graded blood flow restriction.

To quantify the acute effects of graded blood flow restriction on the interaction between changes in mechanical output, muscle oxygenation trends and perceptual responses to heart rate clamped cycling. Repeated measures. Twenty-five adults (21 men) performed six, 6-min cycling bouts (24 min of recovery) at a clamped heart rate corresponding to their first ventilatory threshold at 0 % (unrestricted), 15 %, 30 %, 45 %, 60 % and 75 % of arterial occlusion pressure with the cuffs inflated bilaterally from the fourth to the sixth minute. Power output, arterial oxygen saturation (pulse oximetry) and vastus lateralis muscle oxygenation (near-infrared spectroscopy) were monitored during the final 3 min of pedalling, whilst perceptual responses (modified Borg CR10 scales) were obtained immediately after exercise. Compared to unrestricted cycling, average power output for minutes 4-6 decreased exponentially for cuff pressures ranging 45-75 % of arterial occlusion pressure (P < 0.001). Peripheral oxygen saturation averaged ∼96 % across all cuff pressures (P = 0.318). Deoxyhemoglobin changes were larger at 45-75 % versus 0 % of arterial occlusion pressure (P < 0.05), whereas higher total haemoglobin values occurred at 60-75 % of arterial occlusion pressure (P < 0.05). Sense of effort, ratings of perceived exertion, pain from cuff pressure, and limb discomfort were exaggerated at 60-75 % versus 0 % of arterial occlusion pressure (P < 0.001). Blood flow restriction of at least 45 % of arterial occlusion pressure is required to reduce mechanical output during heart rate clamped cycling at the first ventilatory threshold. Whilst power decreases non-linearly above this pressure threshold, higher occlusion levels ranging 60-75 % of arterial occlusion pressure also accentuate muscle deoxygenation and exercise-related sensations.

Age alters the thermoregulatory responses to extreme heat exposure with accompanying activities of daily living.

Older adults are at greater risk for heat-related morbidity and mortality, due in part to age-related reductions in heat dissipating capabilities. Previous studies investigating the impact of age on responses to heat stress used approaches that lack activities of daily living and therefore may not accurately depict the thermal/physiological strain that would occur during actual heatwaves. We sought to compare the responses of young (18-39 yr) and older (≥65 yr) adults exposed to two extreme heat simulations. Healthy young (n = 20) and older (n = 20) participants underwent two 3-h extreme heat exposures on different days: 1) DRY (47°C and 15% humidity) and 2) HUMID (41°C and 40% humidity). To mimic heat generation comparable with activities of daily living, participants performed 5-min bouts of light physical activity dispersed throughout the heat exposure. Measurements included core and skin temperatures, heart rate, blood pressure, local and whole body sweat rate, forearm blood flow, and perceptual responses. Δ core temperature (Young: 0.68 ± 0.27°C vs. Older: 1.37 ± 0.42°C; P < 0.001) and ending core temperature (Young: 37.81 ± 0.26°C vs. Older: 38.15 ± 0.43°C; P = 0.005) were greater in the older cohort during the DRY condition. Δ core temperature (Young: 0.58 ± 0.25°C vs. Older: 1.02 ± 0.32°C; P < 0.001), but not ending core temperature (Young: 37.67 ± 0.34°C vs. Older: 37.83 ± 0.35°C; P = 0.151), was higher in the older cohort during the HUMID condition. We demonstrated that older adults have diminished thermoregulatory responses to heat stress with accompanying activities of daily living. These findings corroborate previous reports and confirm epidemiological data showing that older adults are at a greater risk for hyperthermia.NEW & NOTEWORTHY Using an experimental model of extreme heat exposure that incorporates brief periods of light physical activity to simulate activities of daily living, the extent of thermal strain reported herein more accurately represents what would occur during actual heatwave conditions. Despite matching metabolic heat generation and environmental conditions, we show that older adults have augmented core temperature responses, likely due to age-related reductions in heat dissipating mechanisms.

Exploring perceptual sensitivity and response bias in the visual periphery

Exploring perceptual sensitivity and response bias in the visual periphery

Cognitive control subprocess deficits and compensatory modulation mechanisms in patients with frontal lobe injury revealed by EEG markers: a basic study to guide brain stimulation

BackgroundFrontal lobe injury (FLI) is related to cognitive control impairments, but the influences of FLI on the internal subprocesses of cognitive control remain unclear.AimsWe sought to identify specific biomarkers for...

Diverse types of expertise in facial recognition

Facial recognition errors can jeopardize national security, criminal justice, public safety and civil rights. Here, we compare the most accurate humans and facial recognition technology in a detailed lab-based evaluation and international proficiency test for forensic scientists involving 27 forensic departments from 14 countries. We find striking cognitive and perceptual diversity between naturally skilled super-recognizers, trained forensic examiners and deep neural networks, despite them achieving equivalent accuracy. Clear differences emerged in super-recognizers’ and forensic examiners’ perceptual processing, errors, and response patterns: super-recognizers were fast, biased to respond ‘same person’ and misidentified people with extreme confidence, whereas forensic examiners were slow, unbiased and strategically avoided misidentification errors. Further, these human experts and deep neural networks disagreed on the similarity of faces, pointing to differences in their representations of faces. Our findings therefore reveal multiple types of facial recognition expertise, with each type lending itself to particular facial recognition roles in operational settings. Finally, we show that harnessing the diversity between individual experts provides a robust method of maximizing facial recognition accuracy. This can be achieved either via collaboration between experts in forensic laboratories, or most promisingly, by statistical fusion of match scores provided by different types of expert.

The Physiological and Perceived Impact of Wearing a Face Mask During Maximal Exercise

The COVID-19 pandemic prompted the expectation of facemasks in fitness facilities during exercise. However, the physiological and perceptual responses of wearing a facemask during exercise has not been fully investigated. The purpose of this study was to determine the effect of facemasks on selected physiological and subjective variables during exercise. Using a crossover design, males (n =8) and females (n=7) and were randomly assigned to (1) a surgical facemask, (2) a cloth face mask, and (3) no mask and completed Bruce Protocol maximal graded treadmill tests 48 hrs apart. Collected data included heart rate (HR), oxyhemoglobin saturation (SpO2), rating of perceived dyspnea (DYS), perceived rate of exertion (RPE) and time to exhaustion (TTE). No significant (p&gt;0.05) differences were found for HR or SpO2 at any of the treadmill stages. DYS was higher with both masks compared to no mask, but only significant (p &lt; 0.05) between the cloth and no mask conditions in stages 2 and 3. RPE was greater in both mask conditions compared to no masks, but only significantly greater between the cloth mask and no mask conditions in stage 3. No significant differences were found for TTE among the conditions. Wearing face masks during exercise and has little effect on HR, SpO2, or TTE. However, facemasks may negatively influence DYS and RPE contributing to feelings of exhaustion. Participants should be made aware that the discomfort of wearing a mask during exercise will not hamper performance.

Acute effects of static balance exercise combined with different levels of blood flow restriction on motor performance fatigue as well as physiological and perceptual responses in young healthy males and females

PurposeThis study investigated the acute effects of a static balance exercise combined with different blood flow restriction (BFR) pressures on motor performance fatigue development and recovery as well as physiological and perceptual responses during exercise in males and females.MethodsTwenty-four recreational active males (n = 13) and females (n = 11) performed static balance exercise on a BOSU ball (3 sets of 60 s with 30 s rest in-between) on three separate (> 3 days) laboratory visits with three different BFR pressures (80% arterial occlusion pressure [AOP], 40%AOP, 30 mmHg [SHAM]) in random order. During exercise, activity of various leg muscles, vastus lateralis muscle oxygenation, and ratings of effort and pain perception were recorded. Maximal squat jump height was measured before, immediately after, 1, 2, 4, and 8 min after exercise to quantify motor performance fatigue development and recovery.ResultsQuadriceps muscle activity as well as ratings of effort and pain were highest, while muscle oxygenation was lowest in the 80%AOP compared to the 40%AOP and SHAM condition, with no differences in postural sway between conditions. Squat jump height declined after exercise with the highest reduction in the 80%AOP (− 16.4 ± 5.2%) followed by the 40%AOP (− 9.1 ± 3.2%), and SHAM condition (− 5.4 ± 3.3%). Motor performance fatigue was not different after 1 min and 2 min of recovery in 40% AOP and 80% AOP compared to SHAM, respectively.ConclusionStatic balance exercise combined with a high BFR pressure induced the largest changes in physiological and perceptual responses, without affecting balance performance. Although motor performance fatigue was increased by BFR, it may not lead to long-term impairments in maximal performance.

Persistent Contralateral Pain Compromises Exercise Tolerance but Does not Alter Corticomotor Responses During Repeated, Submaximal Isometric Knee Extensions to Task Failure

Muscle pain is an important determinant of exercise tolerance, but its relationship with neurophysiological responses during a submaximal exercise trial is unclear. The purpose of this study was to determine the effect of persistent contralateral pain on neurophysiological function and perceptual responses during ipsilateral isometric knee extensions to task failure. Ten participants performed a single-leg repeated submaximal isometric knee extensions with (PAIN) or without (CTRL) constant pain induced by intermittent blood flow occlusion combined with evoked muscle contraction applied to the contralateral, resting leg. Transcranial magnetic stimulation (TMS) applied over the motor cortex was used to assess corticospinal excitability (quantified as motor evoked potentials), corticospinal inhibition (quantified as silent period duration), and short interval intracortical inhibition. Maximal voluntary contractions (MVCs), coupled with femoral nerve stimulation to the exercising leg, were performed every 12 submaximal contractions to assess neuromuscular function. Perceived leg pain and effort were also assessed throughout the exercise. The experimental pain shortened the time to task failure compared to CTRL (P = 0.019). Although time effects were present, no differences appeared between conditions for MVC force, voluntary activation, or potentiated twitch force across both tasks (all P > 0.05). Additionally, no differences between CTRL and PAIN were demonstrated for any TMS-derived measures assessing corticospinal responses. Exercising leg pain was higher in CTRL (P = 0.018), as was perceived exertion (P = 0.030). Overall, when using a persistent, submaximal experimental pain intervention, it appears that although muscle pain compromises exercise tolerance, this phenomenon occurs independently of potential alterations in corticomotor mechanisms.

Perceived timing of postural instability onset

BackgroundThis study investigates the perceived onset of postural instability, a critical aspect of balance. Prior research using Temporal Order Judgment (TOJ) tasks revealed that postural perturbations must occur significantly earlier than an auditory reference stimulus for individuals to perceive them as simultaneous. However, there are methodological concerns with this previous work, particularly an unbalanced stimulus onset asynchrony (SOA) distribution. Research questionDoes the point of subjective simultaneity (PSS) between postural perturbation onset and an auditory reference stimulus differ between SOA distributions unequally (distribution 1) and equally (distribution 2) distributed around true simultaneity (0 ms)? MethodsA repeated measures design was employed, presenting two different SOA distributions to 10 participants using a TOJ task during both distribution 1 (88 trials) and distribution 2 (72 trials) SOA distributions. Paired t-tests were used to determine if there was a significant difference between the PSS of distribution 1 and 2. One-sample t-tests were also performed on the PSS values of both conditions in comparison to 0 ms (defined as true simultaneity) to determine if perceptual responses were delayed. ResultsDistribution 1 led to a perceived delay of postural instability onset by 20.34 ms, while distribution 2 resulted in a perceived delay of the auditory stimulus of 3.52 ms. However, neither condition was significantly different from each other nor from true simultaneity. SignificanceThese findings suggest that the perception of postural instability onset is not slow, contrary to previous beliefs, and emphasize the importance of controlling methodological parameters when examining sensory cues. This understanding will help inform falls prevention strategies.

Priming of the autonomic nervous system after an experimental human pain model.

Modulated autonomic responses to noxious stimulation have been reported in experimental and clinical pain. These effects are likely mediated by nociceptive sensitization, but may also, more simply reflect increased stimulus-associated arousal. To disentangle between sensitization- and arousal-mediated effects on autonomic responses to noxious input, we recorded sympathetic skin responses (SSRs) in response to 10 pinprick and heat stimuli before (PRE) and after (POST) an experimental heat pain model to induce secondary hyperalgesia (EXP) and a control model (CTRL) in 20 healthy females. Pinprick and heat stimuli were individually adapted for pain perception (4/10) across all assessments. Heart rate (HR), heart rate variability (HRV) and skin conductance (SCL) were assessed before, during, and after the experimental pain model. Both pinprick- and heat-induced SSRs habituated from PRE to POST in CTRL, but not EXP (p=0.033). Background SCL (during stimuli application) was heightened in EXP compared to CTRL condition during pinprick and heat stimuli (p=0.009). Our findings indicate that enhanced SSRs after an experimental pain model are neither fully related to subjective pain, as SSRs dissociated from perceptual responses, nor to nociceptive sensitization, as SSRs were enhanced after both modalities. Our findings can, however, be explained by priming of the autonomic nervous system during the experimental pain model, which makes the autonomic nervous system more susceptible to noxious input. Taken together, autonomic readouts have the potential to objectively assess not only nociceptive sensitization, but also priming of the autonomic nervous system, which may be involved in the generation of distinct clinical pain phenotypes.

How visible street greenery moderates traffic noise to improve acoustic comfort in pedestrian environments

The effects of street greenery on the perceptual response to the acoustic comfort of pedestrian streets in traffic noise environments were examined through an experimental study that considered an audio-visual environment with no/low, medium, and high street greenery, dominated by road traffic, anthropogenic, and natural sounds. The results showed that the differences in the acoustic comfort evaluations without and with medium or high greenery were statistically significant. Under the effects of greenery, the acoustic comfort evaluation of each sound type dominating the environments without greenery increased by as much as one level, based on a five-point ordinal category scale. Considering various greenery conditions, dominant sound sources, and environmental functions, greenery was the most significant factor affecting acoustic comfort, and evaluations of pedestrian environments without greenery increased more in leisure environments (0.65–1.42) than in transportation environments (0.45–1.29) when road traffic sounds were at lower levels (50, 55, and 60 dBA) and anthropogenic and natural sounds were predominantly heard and influenced by street greenery. However, sound levels were the most significant factor affecting acoustic comfort when road traffic at 50–70 dBA was predominantly heard. Based on the negative linear relationships between sound levels and acoustic comfort evaluations for no/low, medium, and high greenery conditions, the evaluations affected by greenery increased with the increase in road traffic sound levels in transportation environments, whereas those influenced by either high or medium greenery in leisure environments tended to decrease gradually. These audio-visual perception-based findings provide reference guidance for PE quality optimization and related urban design considering comfortable sound environments.

An embodiment of the cinematographer: emotional and perceptual responses to different camera movement techniques.

We investigate the relationship between camera movement techniques and cognitive responses in audiences, reporting on an experiment exploring the effects of different camera movement methods on viewers' degree of immersion and emotional response. This follows directly from preceding experimental literature and is further motivated by accounts and experiences of practicing cinematographers (authors included), which indicates a correspondence between the two. We designed three different cinematic scenes with indifferent moods, and shot each one time with Steadicam, dolly, handheld, and static camera, resulting in 12 different clips. A total of 44 non-professional participants watched the clips and rated their reactions in terms of arousal and degree of involvement. Experimental results are mixed: movement affects the sense of involvement but not necessarily emotional response. We present and discuss some further explorative results and possible future directions to improve the design. We argue in this contribution that there is value in experimental approaches to cinematography, enabling the systematic study of creative intuitions and audience responses in controlled settings.

Dynamic State-Space Modeling With Factorial Memories in Temporal Dominance of Sensations, Emotions and Temporal Liking

There are few mathematical models that describe how human perceptual and affective responses evolve with time. We developed a state-space model of the interrelationships based on time-evolving perceptual and affective responses acquired by the temporal dominance (TD) method. We defined and computed the state variables that endow the system with memory using canonical variate analysis. Furthermore, we determined the model parameters on the basis of a cross-validation approach such that the observed and estimated changes in the affective responses are highly correlated. We applied this method to the TD curves of responses to eating strawberries and plum pickles, reported in our previous work. The model describes what happens during food intake in terms of a few state variables that summarize a large number of observable responses reductively, thus helping to make the perceptual and affective dynamics understandable.

An embodiment of the Cinematographer: emotional and perceptual responses to different camera movement techniques

An embodiment of the Cinematographer: emotional and perceptual responses to different camera movement techniques

Defocus flicker of chromatic stimuli deactivates accommodation.

Tunable lenses, optical elements able to change their optical power within milliseconds, constitute an emerging technology increasingly used in ophthalmic applications. In this study, 25 subjects looked through tunable lenses at a chromatic stimulus to evaluate the perceptual response of the human visual system to periodic changes in defocus of 0.25D of amplitude and 15 Hz of temporal frequency. These defocus changes produce flicker and chromatic distortions that change with the overall level of defocus. The task in this study was to minimize the flicker by varying the average optical power, and it was performed for different myopic and hyperopic starting points. Subjects also performed a blur-minimization task in a black-and-white stimulus of the same geometry. The flicker-minimization task is more repeatable than the blur-minimization task (standard deviations ±0.17D and ±0.49D). The time per repetition of the flicker-minimization task is only 38s. Cycloplegia severely affects the blur-minimization, but not the flicker-minimization task, confirming that defocus flicker deactivates the accommodative system. This discovery can be used to develop new methods for measuring the refractive error of the eye that does not require supervision and can potentially improve existing subjective methods in terms of accuracy, precision, and measurement time.

Responses to Exercise at the Critical Heart Rate vs. the Power Output Associated With the Critical Heart Rate.

Succi, PJ, Dinyer-McNeely, TK, Voskuil, CC, Abel, MG, Clasey, JL, and Bergstrom, HC. Responses to exercise at the critical heart rate vs. the power output associated with the critical heart rate. J Strength Cond Res XX(X): 000-000, 2023-This study examined the physiological (volume of oxygen consumption [V̇o2], heart rate [HR], power output [PO], respiration rate [RR], muscle oxygen saturation [%SmO2]), neuromuscular (electromyographic and mechanomyographic amplitude [EMG AMP and MMG AMP] and mean power frequency [EMG MPF and MMG MPF]), and perceptual (rating of perceived exertion [RPE]) responses during exercise anchored at the critical heart rate (CHR) vs. the PO associated with CHR (PCHR). Nine subjects (mean ± SD; age = 26 ± 3 years) performed a graded exercise test and 4 constant PO trials to exhaustion at 85-100% of peak PO (PP) to derive CHR and PCHR on a cycle ergometer. Responses were recorded during trials at CHR (173 ± 9 b·min-1, time to exhaustion [TLim] = 45.5 ± 20.2 minutes) and PCHR (198 ± 58 W, TLim = 21.0 ± 17.8 minutes) and normalized to their respective values at PP in 10% intervals. There were significant (p ≤ 0.05) mode (CHR vs. PCHR) × time (10%-100% TLim) interactions for all variables (p < 0.001-0.036) except MMG AMP (p > 0.05). Post hoc analyses indicated differences across time for CHR V̇o2 (%change = -22 ± 16%), PCHR V̇o2 (19 ± 5%), CHR RR (24 ± 23%), PCHR RR (45 ± 14%), CHR PO (-33 ± 11%), PCHR HR (22 ± 5%), CHR RPE (22 ± 14%), PCHR RPE (39 ± 6%), CHR %SmO2 (41 ± 33%), PCHR %SmO2 (-18 ± 40%), CHR EMG AMP (-13 ± 15%), PCHR EMG AMP (13 ± 13%), CHR EMG MPF (9 ± 8%), CHR MMG MPF (7 ± 11%), and PCHR MMG MPF (-3 ± 14%). The critical heart rate was more sustainable than PCHR but required adjustments in PO which traversed intensity domains and caused dissociations of the responses previously observed in exercise anchored to PO. These dissociations indicated the demands to exercise varied with anchoring scheme and provides an important consideration for practitioners prescribing endurance exercise.