The purpose of this article was to (i) compare different modes of feedback (multiple vs. single) on 30 min cycling time-trial performance in non-cyclist's and cyclists-triathletes, and (ii) ...investigate cyclists-triathlete's information acquisition.
20 participants (10 non-cyclists, 10 cyclists-triathletes) performed two 30 min self-paced cycling time-trials (TT, ∼5-7 days apart) with either a single feedback (elapsed time) or multiple feedback (power output, elapsed distance, elapsed time, cadence, speed, and heart rate). Cyclists-triathlete's information acquisition was also monitored during the multiple feedback trial via an eye tracker. Perceptual measurements of task motivation, ratings of perceived exertion (RPE) and affect were collected every 5 min. Performance variables (power output, cadence, distance, speed) and heart rate were recorded continuously.
Cyclists-triathletes average power output was greater compared to non-cyclists with both multiple feedback (227.99 ± 42.02 W; 137.27 ± 27.63 W
< 0.05) and single feedback (287.9 ± 60.07 W; 131.13 ± 25.53 W). Non-cyclist's performance did not differ between multiple and single feedback (
> 0.05). Whereas, cyclists-triathletes 30 min cycling time-trial performance was impaired with multiple feedback (227.99 ± 42.02 W) compared to single feedback (287.9 ± 60.07 W;
< 0.05), despite adopting and reporting a similar pacing strategy and perceptual responses (
> 0.05). Cyclists-triathlete's primary and secondary objects of regard were power (64.95 s) and elapsed time (64.46 s). However, total glance time during multiple feedback decreased from the first 5 min (75.67 s) to the last 5 min (22.34 s).
Cyclists-triathletes indoor 30 min cycling TT performance was impaired with multiple feedback compared to single feedback. Whereas non-cyclist's performance did not differ between multiple and single feedback. Cyclists-triathletes glanced at power and time which corresponds with the wireless sensor networks they use during training. However, total glance time during multiple feedback decreased over time, and therefore, overloading athletes with feedback may decrease performance in cyclists-triathletes.
Purpose
To investigate the effects of 60 min daily, short-term (STHA) and medium-term (MTHA) isothermic heat acclimation (HA) on the physiological and perceptual responses to exercise heat stress.
...Methods
Sixteen, ultra-endurance runners (female = 3) visited the laboratory on 13 occasions. A 45 min sub-maximal (40%
W
max
) cycling heat stress test (HST) was completed in the heat (40 °C, 50% relative humidity) on the first (HST
PRE
), seventh (HST
STHA
) and thirteenth (HST
MTHA
) visit. Participants completed 5 consecutive days of a 60 min isothermic HA protocol (target
T
re
38.5 °C) between HST
PRE
and HST
STHA
and 5 more between HST
STHA
and HST
MTHA
. Heart rate (HR), rectal (
T
re
), skin (
T
sk
) and mean body temperature (
T
body
), perceived exertion (RPE), thermal comfort (TC) and sensation (TS) were recorded every 5 min. During HSTs, cortisol was measured pre and post and expired air was collected at 15, 30 and 45 min.
Results
At rest,
T
re
and
T
body
were lower in HST
STHA
and HST
MTHA
compared to HST
PRE,
but resting HR was not different between trials. Mean exercising
T
re
,
T
sk
,
T
body
, and HR were lower in both HST
STHA
and HST
MTHA
compared to HST
PRE
. There were no differences between HST
STHA
and HST
MTHA
. Perceptual measurements were lowered by HA and further reduced during HST
MTHA
.
Conclusion
A 60 min a day isothermic STHA was successful at reducing physiological and perceptual strain experienced when exercising in the heat; however, MTHA offered a more complete adaptation.
Objective
To compare the thermographic pattern of regions of interest (ROI) of respiratory muscles in young asthmatics with and without bronchospasm induced by eucapnic voluntary hyperpnea (EVH).
...Materials and Methods
Cross‐sectional study carried out with 55 young (55% male and 45% females) aged 12.5 ± 3.3 years, divided in nine nonasthmatics, 22 asthmatics without exercise‐induced bronchospasm compatible response (EIB‐cr) and 24 asthmatics with EIB‐cr. The diagnosis of EIB was given to subjects with a fall in forced expiratory volume in the first second (FEV1) ≥ 10% compared to baseline. Thermographic recordings of respiratory muscles were delimited in ROI of the sternocleidomastoid (SCM), pectoral, and rectus abdominis intention area. Thermal captures and FEV1 were taken before and 5, 10, 15 and 30 min after EVH.
Results
Twenty‐four (52.1%) of asthmatics had EIB‐cr. There was a decrease in temperature at 10 min after EVH test in the SCM, pectoral and rectus abdominis ROIs in all groups (both with p < 0.05). There was a decrease in temperature (% basal) in asthmatic with EIB‐cr compared to nonasthmatics in the rectus abdominis area (p < 0.05).
Conclusion
There was a decrease in temperature in the ROIs of different muscle groups, especially in asthmatics. The greater drop in FEV1 observed in individuals with EIB‐cr was initially associated with a decrease in skin temperature, with a difference between the nonasthmatics in the abdominal muscle area. It is likely that this decrease in temperature occurred due to a temporary displacement of blood flow to the most used muscle groups, with a decrease in the region of the skin evaluated in the thermography.
To investigate cooling strategies employed by athletes (cyclists-triathletes) during training and competition in hot and dry (HD) and hot and humid (HH) conditions.
Thirty-five athletes completed an ...online questionnaire on the type, timing, and justification of cooling strategies employed during past training and/or competitions in HD and HH conditions. In addition, 3 athletes also completed a one-to-one follow-up interview.
Comparisons between strategies employed in all conditions were based on
= 14 (40%). Cold-water pouring was the most employed (
= 4; 21%) strategy during training and/or competing in hot conditions. The timing of the strategies employed was based on pitstops only (
= 7; 50%). The justification for strategies employed was based on trial and error (
= 9, 42.85%:
= 10, 47.61%). All athletes rated strategies employed as 1 ("not effective for minimising performance impairments and heat-related illnesses"). Comparisons between HD and HH were based on
= 21 (60%), who employed different strategies based on condition. Cold-water ingestion was the most employed (
= 9, 43%) strategy in HD, whereas a combination of cold-water ingestion and pouring was the most employed (
= 9, 43%) strategy in HH. The timing of strategies employed in the HD split was pre-planned by distance but was modified based on how athletes felt during (
= 8, 38%), and pre-planned by distance and pit stops (
= 8, 38%). The timing of strategies employed in HH was pre-planned based on distance and how athletes felt during (
= 9, 42%). About 57% (
= 12) of the 60% (
= 21) perceived effectiveness in HD and HH as 3 ("
), whereas 43% (
= 9) of the 60% (
= 21) perceived effectiveness in HD and HH as 4 ("
").
Cold-water ingestion is the preferred strategy by athletes in HD compared to a combination of cold-water ingestion and pouring in HH conditions. All strategies were pre-planned and trialled based on distance and how athletes felt during training and/or competition. These strategies were perceived as effective for minimising performance impairments, but not heat-related illnesses. Future studies should evaluate the effectiveness of these cooling strategies on performance and thermoregulatory responses in HD and HH conditions.
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