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Salivary Cortisol, Heart Rate, and Blood Lactate Responses During Elite Downhill Mountain Bike Racing

Billy Sperlich, Silvia Achtzehn, Mirijam Buhr, Christoph Zinner, Stefan Zelle, and Hans-Christer Holmberg

Purpose:

This study aimed to quantify the intensity profile of elite downhill mountain bike races during competitions.

Methods:

Seventeen male downhill racers (22 ± 5 y; 185.1 ± 5.3 cm; 68.0 ± 3.9 kg; VO2peak: 59.4 ± 4.1 mL·min·kg−1) participated in the International German Downhill Championships in 2010. The racers’ peak oxygen uptake and heart rate (HR) at 2 and 4 mmol·L−1 blood lactate (HR2 and HR4), were assessed during an incremental laboratory step test (100 W, increase 40 W every 5 min). During the races, the HR was recorded and pre- and postrace blood lactate concentrations as well as salivary cortisol levels were obtained.

Results:

During the race, the absolute time spent in the “easy” intensity zone was 23.3 ± 6.8 s, 24.2 ± 12.8 s (HR2–HR4) in the “moderate” zone, and 151.6 ± 18.3 s (>HR4) in the “hard” zone. Eighty percent of the entire race was accomplished at intensities >90% HRpeak. Blood lactate concentrations postrace were higher than those obtained after the qualification heat (8.0 ± 2.5 mmol·L−1 vs 6.7 ± 1.8 mmol·L−1, P < .01). Salivary levels of cortisol before the competition and the qualification heat were twice as high as at resting state (P < .01).

Conclusions:

This study shows that mountain bike downhill races are conducted at high heart rates and levels of blood lactate as well as increased concentration of salivary cortisol as marker for psycho-physiological stress.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 7 (2012): Issue 1 (Mar 2012)

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Lack of Association between Indices of Vitamin B1, B2, and B6, Status and Exercise-Induced Blood Lactate in Young Adults

Mikael Fogelholm, Inkeri Ruokonen, Juha T. Laakso, Timo Vuorimaa, and Jaakko-Juhani Himberg

By means of a 5-week vitamin B-complex .supplementation, associations between indices of vitamin B1, B2, and B6, status (activation coefficients [AC] for erythrocyte transketolase, glutathione reductase, and aspartate aminotransferase) and exercise-induced blood lactate concentration were studied. Subjects, 42 physically active college students (18–32 yrs), were randomized into vitamin (n=22) and placebo (n=20) groups. Before the supplementation there were no differences in ACs or basal enzyme activities between the groups. The ACs were relatively high, suggesting marginal vitamin status. In the vitamin group, all three ACs were lower (p<0.0001) after supplementation: transketolase decreased from l. 16 (1.14–1.18) (mean and 95% confidence interval) to 1.08 (1.06–1.10); glutathione reductase decreased from 1.33 (1.28–1.39) to 1 .I4 (1.1 1–1.17); and aspartate aminotransferase decreased from 2.04 (1.94–2.14) to 1.73 (1.67–1.80). No changes were found after placebo. Despite improved indices of vitamin status, supplementation did not affect exercise-induced blood lactate concentration. Hence no association was found between ACs and blood lactate. It seems that marginally high ACs do not necessarily predict altered lactate metabolism.

Cover International Journal of Sport Nutrition and Exercise Metabolism

In International Journal of Sport Nutrition and Exercise Metabolism Volume 3 (1993): Issue 2 (Jun 1993)

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Blood Lactate Responses of Male and Female Players Across an International Rugby Sevens Tournament

Carl James, James Rees, Henry Chong, Lee Taylor, Christopher M. Beaven, Mitch Henderson, and Julien S. Baker

monitoring. 6 , 7 Granatelli et al 6 reported mean (SD) blood lactate concentrations [La − ] from 4 players at the 2010 and 2011 Rome international tournaments. Values of 8.7 (1.7) and 11.2 (1.4) mmol·L −1 were measured 2 minutes after half-time and match finish, respectively. Couderc et al 7 later

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 18 (2023): Issue 9 (Sep 2023): Special Issue: Rugby World Cup 2023—Physiology and Performance Research

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Comparison of 4 Different Cooldown Strategies on Lower-Leg Temperature, Blood Lactate Concentration, and Fatigue Perception After Intense Running

Junhyeong Lim, Hyeongjun Park, Seunghee Lee, and Jihong Park

-intensity movement (eg, walking or jogging). 9 An increased blood flow is thought to be the mechanism, which facilitates the removal of blood lactate concentration due to the elimination of blood H + 10 and activation of oxidation. 11 Previous studies on CWI have also reported effectiveness in reducing fatigue

Cover Journal of Sport Rehabilitation

In Journal of Sport Rehabilitation Volume 31 (2022): Issue 8 (Nov 2022)

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Peak Blood Lactate Concentration and Its Arrival Time Following Different Track Running Events in Under-20 Male Track Athletes

Subir Gupta, Arkadiusz Stanula, and Asis Goswami

physiological parameters that influence long-distance running performance are maximal oxygen consumption (VO 2 max), running economy, and fractional utilization of aerobic capacity. 2 A number of studies have been conducted to find out the most appropriate time for the measurement of peak blood lactate

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 16 (2021): Issue 11 (Nov 2021)

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Acute Response to One Bout of Dynamic Standing Exercise on Blood Glucose and Blood Lactate Among Children and Adolescents With Cerebral Palsy Who are Nonambulant

Petra Lundström, Katarina Lauruschkus, Åsa Andersson, and Åsa B. Tornberg

tissue hypoxia is absent. Mild hyperlactatemia has been defined as persistent increase in blood lactate concentration (≥2.1–5 mmol/L) ( 8 ), whereas, lactic acidosis is defined as metabolic acidosis (≥5 mmol) ( 8 ). CP is a permanent heterogeneous disorder caused by a lesion in the immature brain ( 30

Cover Pediatric Exercise Science

In Pediatric Exercise Science Volume 34 (2022): Issue 2 (May 2022)

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No Influence of Acute Moderate Normobaric Hypoxia on Performance and Blood Lactate Concentration Responses to Repeated Wingates

Naoya Takei, Katsuyuki Kakinoki, Olivier Girard, and Hideo Hatta

, only one study examined the effects of acute moderate and severe hypoxia (inspired fraction of oxygen or FiO 2 of 0.164 and 0.136, respectively) versus normoxia on RW performance (4 × 30-s Wingate efforts with 4-min recovery). 10 In this previous study, blood lactate concentration (BLa) was only

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 16 (2021): Issue 1 (Jan 2021)

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Heart Rate–Blood Lactate Profiling in World-Class Biathletes During Cross-Country Skiing: The Difference Between Laboratory and Field Tests

Craig A. Staunton, Erik P. Andersson, Glenn Björklund, and Marko S. Laaksonen

and metabolic intensity domains. 3 For example, a common metabolic marker of exercise intensity is the concentration of blood lactate ([La]), where HR zones are designed to reflect various levels of [La]. 1 Elite-level athletes regularly perform laboratory-based testing sessions where they complete

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 18 (2023): Issue 7 (Jul 2023)

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Four Days of Blueberry Powder Supplementation Lowers the Blood Lactate Response to Running But Has No Effect on Time-Trial Performance

Jason P. Brandenburg and Luisa V. Giles

period, an incremental exercise test was then conducted to determine VO 2 max. The final three visits served as experimental sessions. In each experimental session, participants completed an 8-km TT. Blood lactate, CMVJ, and DJ were assessed before the TT and during a 30-min recovery period. Saliva

Cover International Journal of Sport Nutrition and Exercise Metabolism

In International Journal of Sport Nutrition and Exercise Metabolism Volume 29 (2019): Issue 6 (Nov 2019)

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Blood Lactate Concentration and Clearance in Elite Swimmers During Competition

Jason D. Vescovi, Olesya Falenchuk, and Greg D. Wells

Purpose:

Blood lactate concentration, [BLa], after swimming events might be influenced by demographic features and characteristics of the swim race, whereas active recovery enhances blood lactate removal. Our aims were to (1) examine how sex, age, race distance, and swim stroke influenced [BLa] after competitive swimming events and (2) develop a practical model based on recovery swim distance to optimize blood lactate removal.

Methods:

We retrospectively analyzed postrace [BLa] from 100 swimmers who competed in the finals at the Canadian Swim Championships. [BLa] was also assessed repeatedly during the active recovery. Generalized estimating equations were used to evaluate the relationship between postrace [BLa] with independent variables.

Results:

Postrace [BLa] was highest following 100–200 m events and lowest after 50 and 1500 m races. A sex effect for postrace [BLa] was observed only for freestyle events. There was a negligible effect of age on postrace [BLa]. A model was developed to estimate an expected change in [BLa] during active recovery (male = 0; female = 1): [BLa] change after active recovery = –3.374 + (1.162 × sex) + (0.789 × postrace [BLa]) + (0.003 × active recovery distance).

Conclusions:

These findings indicate that swimmers competing at an elite standard display similar postrace [BLa] and that there is little effect of age on postrace [BLa] in competitive swimmers aged 14 to 29 y.

Cover International Journal of Sports Physiology and Performance

In International Journal of Sports Physiology and Performance Volume 6 (2011): Issue 1 (Mar 2011)