Dry blood spot samples to monitor immune-associated mRNA expression in intervention studies: Impact of Baker's yeast beta glucan.

Monitoring immunological response to physical stressors in a field setting is challenging because existing methods require a laboratory visit and traditional blood collection via venipuncture. The purpose of this study was to determine if our optimized dry blood spot (DBS) methodology yields sufficient total RNA to quantify the effect of Baker's Yeast Beta Glucan supplementation (BYBG; Wellmune; 250 mg/d) on post-exercise mRNA expression. Participants had venous DBS samples collected prior to (PRE), and immediately (POST), 2 (2H), and 4 (4H) hrs after completion of a 90 min run/walk trial in a hot, humid environment. Total RNA extracted from DBS was analyzed using a 574-plex Human Immunology mRNA panel (Nanostring). BYBG supplementation was associated with the increased expression of 12 mRNAs (LTB4R, PML, PRFM1, TNFRSF14, LCK, MYD88, STAT3, CCR1, TNFSF10, LILRB3, MME, and STAT6) and decreased expression of 4 mRNAs (MAP4K1, IKBKG, CD5, and IL4R) across all post-exercise time points. In addition to individually changed mRNA targets, we found eleven immune-response pathways that were significantly enriched by BYBG following exercise (TNF Family signaling, immunometabolism, oxidative stress, toll-like receptor (TLR) signaling, Treg differentiation, autophagy, chemokine signaling, complement system, Th2 differentiation, cytokine signaling, and innate immune). The present approach showed that DBS samples can be used to yield useful information about mRNA biomarkers in an intervention study. We have found that BYBG supplementation induces changes at the mRNA level that support the immune system and reduce susceptibility to opportunistic infection (i.e., upper respiratory tract infection) and facilitate improved physical recovery from exercise. Future studies may look to use DBS sampling for testing other nutritional, health, or medical interventions.

A Physiological Anchor for the Perception of Effort.

This is a two-part study to determine one or more reliable physiological anchors for perception of effort. The purpose of Study 1 was to compare ratings of perceived exertion (RPE) at the ventilatory threshold (VT) in running, cycling, and upper body exercise with the premise that if RPE at VT did not differ across exercise modes, VT might provide a unique set of physiological inputs for perception of effort. For 27 participants, values for VT and for RPE at VT (Borg 6 to 20 scale) averaged 9.4 km⋅h-1 (SD = 0.7) and 11.9 km⋅h-1 (SD = 1.4) respectively in running, 135 W (SD = 24) and 12.1 W (SD = 1.6) in cycling, and 46 W (SD = 5) and 12.0 W (SD = 1.7) in upper body exercise. RPE did not differ, suggesting that VT may anchor effort perception. In Study 2, 10 participants performed cycle ergometer exercise for 30 minutes at their VT (M = 101 W, SD = 21), at their maximal lactate steady state (M = 143 W, SD = 22), and at their critical power (CP; M = 167 W, SD = 23). Mean end-exercise RPE were 12.1 (SD = 2.1), 15.0 (SD = 1.9), and 19.0 (SD = 0.5), respectively. The very close clustering of RPE during exercise at CP hints that the confluence of physiological responses at CP may (also) serve as a determinant in perception of effort.

Pedalling Cadence Affects V̇ o2 Kinetics in Severe-Intensity Exercise.

ABSTRACT: Hill, DW and Vingren, JL. Pedalling cadence affects V̇ o2 kinetics in severe-intensity exercise. J Strength Cond Res 37(6): 1211-1217, 2023-The purpose was to investigate the effects of pedalling cadence on V̇ o2 kinetics in severe-intensity cycling exercise. This question is pertinent to exercise testing, where cadence is an important (and often confounding) variable, and to performance, where V̇ o2 kinetics determines the initial reliance upon anaerobic reserves. Eighteen university students performed tests to exhaustion at 241 ± 31 W, using cadences of 60, 80, and 100 rev·min -1 . V̇ o2 data were fitted to a 2-component model (primary phase + slow component). Responses during the 3 tests were compared using a repeated-measures analysis of variance, with significance at p < 0.05. The mean response time of the primary phase of the V̇ o2 response (time to reach 63% of the response) was progressively smaller (response was faster) at higher cadences (37 ± 4 seconds at 60 rev·min -1 , 32 ± 5 seconds at 80 rev·min -1 , 27 ± 4 seconds at 100 rev·min -1 ), and there was a concomitantly faster heart rate response. In addition, the time delay before the slow component was shorter, the amplitude of the primary phase was greater, and the amplitude of the slow component was smaller at the higher cadence. The results suggest that pedalling cadence itself-and not just the higher metabolic demand associated with higher cadences-may be responsible for differences in temporal characteristics (time delays, time constants) of the primary and slow phases of the V̇ o2 response. Exercise scientists must consider, and coaches might apply, the relationship between V̇ o2 kinetics and pedalling cadence during exercise testing.

Acute Physiological and Perceptual Responses to Rest Redistribution With Heavier Loads in Resistance-Trained Men.

ABSTRACT: Chae, S, Hill, DW, Bailey, CA, Moses, SA, McMullen, SM, and Vingren, JL. Acute physiological and perceptual responses to rest redistribution with heavier loads in resistance-trained men. J Strength Cond Res 37(5): 994-1000, 2023-The purpose of this study was to explore the effect of rest redistribution with heavier loads (RR + L) on physiological and perceptual responses in resistance-trained men. Eight men who had back squat (BS) 1 repetition maximum (1RM) to body mass ratio; 1.8 ± 0.2 completed 2 BS exercise sessions in a counterbalanced and a randomized order; RR + L: 4 sets of (2 × 5) repetitions with 90-second interset rest and 30-second intraset rest using 75% BS 1RM and traditional sets (TS): 4 sets of 10 repetitions with 120-second interset rest using 70% BS 1RM. Blood samples were collected before exercise, immediately post exercise, and 5, 15, and 30 minutes post exercise for the analysis of growth hormone (GH), total testosterone (TT), cortisol (C), and blood lactate (BL), whereas rating of perceived exertion (RPE) and heart rate (HR) were measured immediately after each set of the BS exercise. While neither main effect of condition nor interaction existed, there was a significant ( p < 0.05) main effect of time point (and set) for GH, TT, C, BL, RPE, and HR. Volume load was greater for RR + L compared with TS (4,074.9 ± 786.7 kg vs. 3,796.3 ± 714.8 kg). In conclusion, RR + L increases volume load by approximately 7% but does not seem to influence GH ( g = -0.15), TT ( g = -0.09), BL ( g = -0.22), RPE ( g = 0.14), and HR ( g = -0.08) responses. Practitioners may consider using RR + L to increase volume load without increasing acute fatigue responses.

Physiological response and physical performance after 40 min and 90 min daytime nap opportunities.

This study aimed to examine the impact of 40-min and 90-min naps on performance in the 5-m shuttle run test (5mSRT) and on various physiological and perceptual measures. Sixteen male athletes (20 ± 3 years, 173 ± 7 cm, 67 ± 7 kg) performed the 5mSRT after a 40-min nap (N40), after a 90-min nap (N90), and in a no-nap, control condition (N0). The 5mSRT involves six repetitions of 30 s of all-out exercise. Total distance (in the six repetitions) and highest distance (in a single repetition) in the 5mSRT were greater after naps than in N0 (p < 0.001), and the total distance, which reflects the anaerobic capacity, was greater in N90 than in N40 (p < 0.05). Physiological and perceptual responses were favourable in both nap conditions (p < 0.01), more so in N90 than in N40 (p < 0.05). Together, the results support the contention that physiological/perceptual responses after napping contribute to improved exercise performance and that longer naps are more effective.

Calculation of a conversion factor for estimating the glycolytic contribution in exercise from post-exercise blood lactate concentration.

Purpose: Often, the glycolytic contribution in a bout of heavy or severe intensity exercise is estimated by multiplying the increase in blood lactate concentration above resting levels that is engendered by the exercise (in mM) by 3.3 (or 3) mL·kg-1 per mM. Our purpose was to verify the value of this conversion factor, using methods that were completely different from those of the original studies. Methods: Six women (mean ± SD), age, 23 ± 1 year; VO2max, 46 ± 4 mL·kg-1·min-1) and three men (23 ± 0 years; 54 ± 8 mL·kg-1·min-1) completed 6 min of heavy intensity exercise in conditions of normoxia and hypoxia (FIO2, ∼12%). VO2 was measured throughout the exercise and 7 min of recovery. The increase in glycolytic contribution was estimated as the reduction in aerobic contribution in hypoxia, after correction for the effects of hypoxia on the oxygen demand and on the contribution from phosphocreatine. The peak post-exercise blood lactate concentration was measured in fingerstick blood samples. Results: The ratio between the increase in estimated glycolytic contribution (in mL·kg-1) in hypoxia and the increase in peak blood lactate concentration (in mM) yielded an oxygen equivalent of 3.4 ± 0.4 mL·kg-1 per mM (range, 2.6 mL·kg-1 per mM to 4.0 mL·kg-1 per mM) for cycle ergometer exercise. Conclusion: These results generally support the use of a common conversion factor to calculate the glycolytic contribution from post-exercise blood lactate concentrations. However, there is some inter-individual variability in the conversion factor.

Prebiotic/probiotic supplementation resulted in reduced visceral fat and mRNA expression associated with adipose tissue inflammation, systemic inflammation, and chronic disease risk.

BACKGROUND: Prebiotic/probiotic supplementation represents a viable option for addressing elevated systemic inflammation and chronic disease risk in overweight individuals. The purpose of this study was to determine if 90 days of prebiotic/probiotic supplementation could alter mRNA responsible for inflammation and chronic disease risk in weight-stable overweight adults. Nanostring mRNA analysis (574 plex) was used to survey targets associated with adipose tissue inflammation, systemic inflammation, and chronic disease risk. All protocols were approved by the University IRB, and participants gave written informed consent. Participants were randomly assigned to either placebo (N = 7; rice flour) or combined (N = 8) prebiotic (PreticX® Xylooligosaccharide; 0.8 g/day; ADIP) and probiotic (MegaDuo® Bacillus subtilis HU58 and Bacillus coagulans SC-208; billion CFU/day) supplementation. Participants were diverse population of healthy individuals with the exception of excess body weight. Measurements were made at baseline, 30, 60, and 90 days. Whole-body DXA scans (GE iDXA®; body composition) and blood 574-plex mRNA analysis (Nanostring®) were used to generate primary outcomes. Significance was set to p < 0.05 and adjusted for multiple comparisons where necessary. RESULTS: Compared to placebo, prebiotic/probiotic supplementation was associated with a 35% reduction in visceral adipose tissue (VAT; p = 0.002) but no change in body weight or overall percent body fat. Prebiotic/probiotic supplementation resulted in significant (p < 0.05), differential expression of 15 mRNA associated with adipose tissue inflammation (GATA3, TNFAIP6, ST2, CMKLR1, and CD9), systemic inflammation (LTF, SOCS1, and SERPING1), and/or chronic disease risk (ARG1, IL-18, CCL4, CEACAM6, ATM, CD80, and LAMP3). We also found 6 additional mRNA that had no obvious relationship to three previous biological functions (CSF1, SRC, ICAM4CD24, CD274, and CLEC6A). CONCLUSION: The key findings support that 90-day prebiotic/probiotic supplementation may be associated with reduced adipose tissue inflammation, reduced systemic inflammation, and reduced chronic disease risk. Combined with the unexpected finding of reduced VAT, this intervention may have resulted in improved overall health and reduced chronic disease risk.

Longer Nap Duration During Ramadan Observance Positively Impacts 5-m Shuttle Run Test Performance Performed in the Afternoon.

It is well-documented that changes in the rhythm of life during Ramadan affect sleep schedules (i.e., interruption of night sleep patterns) and are likely to have negative effects on physical and cognitive performances. The aim of the present study was to examine the effect of different naps opportunities' durations during Ramadan on performance of short-duration repetitive maximal exercise and perception of effort. Fifteen physically active men (age: 21 ± 3 years, height: 177 ± 6 cm, body-mass: 73 ± 10 kg) performed a 6 × 30-s shuttle run test after a 25-min nap (N25), a 45-min nap (N45), and in a no-nap condition (NN) during three experimental periods: ∼2 weeks before Ramadan (BR), the last ten days of Ramadan (ER), and ∼3 weeks after Ramadan (AR). During the shuttle run test performed in the late afternoon, the greatest distance (GD), the total distance (TD) and a fatigue index (FI) were assessed. Rating of perceived exertion (RPE) was determined after each 30-s effort. Dietary intake and sleep quality were assessed in each of the three periods. Compared to BR, GD and TD were lower in the ER testing period (p = 0.005; d = 0.54) but returned to BR levels in the AR period. During ER, carbohydrate intake was lower (p = 0.04; d = 0.2), and sleep duration and sleep quality were reduced (d = 0.27 and 0.54, respectively), although other aspects of dietary intake and sleep pattern were not affected. Compared to NN, GD and TD were higher after N25 (d = 0.57 and 0.34, respectively) and N45 (d = 0.93 and 0.88 respectively). RPE was lower in N45 (p = 0.035, d = 0.84). N45 resulted in higher TD (p = 0.021, d = 0.13) and lower RPE (p = 0.004; d = 0.57) compared to N25 during ER. Taking a daytime nap benefits subsequent performance in a shuttle run test, whether sleep the previous night was normal (as in BR) or compromised (as in ER). The benefits of napping were greater after a 45-min nap opportunity than after a 25-min nap opportunity.

A daytime 40-min nap opportunity after a simulated late evening soccer match reduces the perception of fatigue and improves 5-m shuttle run performance.

The effect of a 40-min nap opportunity was investigated during the day following a late evening simulated soccer match. Twelve male amateur soccer players (23 ± 3 years; 77.3 ± 5.3 kg; 1.76 ± 0.04 m) performed the Loughborough-intermittent-shuttle test at 21h00 and the following day they completed the sleepiness scale after either a nonap (N0) or 40-min nap (N40) opportunity that began at 14h00. At 17h00, participants performed the 5-m shuttle run test (5mSRT) (6 × 30-s with 35-s in-between; best distance (BD) and total distance (TD) were calculated). After performing the 5mSRT, they provided their rating of the perceived exertion (RPE) and rated their muscle soreness. Sleepiness scores were significantly lower in N40 in comparison with N0 (P < 0.05). A significant increase of TD (+64.5 m) and BD (+9.6 m) after N40 compared to N0 was observed (P < 0.05). The improved performance was associated with reduced levels of muscle soreness and lower RPE. In conclusion, a daytime 40-min nap opportunity after a late evening simulated soccer match improves short-term repetitive maximal performance in soccer players, and has positive effects on perception of sleepiness, muscle soreness, and RPE.

Effect of Previous-Day Alcohol Ingestion on Muscle Function and Performance of Severe-Intensity Exercise.

PURPOSE: Many athletes report consuming alcohol the day before their event, which might negatively affect their performance. However, the effects of previous-day alcohol ingestion on performance are equivocal, in part, due to no standardization of alcohol dose in previous studies. The purpose of this study was to examine the impact of a standardized previous-day alcohol dose and its corresponding impact on morning-after muscular strength, muscular power, and muscular fatigue in a short-duration test and on performance of severe-intensity exercise. METHODS: On 2 occasions, 12 recreationally active individuals reported to the Applied Physiology Laboratory in the evening and ingested a beverage containing either 1.09 g ethanol·kg-1 fat-free body mass (ALC condition) or water (PLA condition). The following morning, they completed a hangover symptom questionnaire, vertical jumps, isometric midthigh pulls, biceps curls, and a constant-power cycle ergometer test to exhaustion. The responses from ALC and PLA were compared using paired-means t tests. RESULTS: Time to exhaustion in the cycle ergometer tests was less (P = .03) in the ALC condition (181 [39] s vs 203 [34] s; -11%, Cohen d = 0.61). There was no difference in performance in vertical jump test, isometric midthigh pulls, and biceps curls tests between the ALC and PLA conditions. CONCLUSIONS: Previous-day alcohol consumption significantly reduces morning-after performance of severe-intensity exercise. Practitioners should educate their athletes, especially those whose events rely on anaerobic capacity and/or a rapid response of the aerobic pathways, of the adverse effect of previous-day alcohol consumption on performance.

Effects of wearing a cloth face mask on performance, physiological and perceptual responses during a graded treadmill running exercise test.

OBJECTIVES: To (1) determine if wearing a cloth face mask significantly affected exercise performance and associated physiological responses, and (2) describe perceptual measures of effort and participants' experiences while wearing a face mask during a maximal treadmill test. METHODS: Randomised controlled trial of healthy adults aged 18-29 years. Participants completed two (with and without a cloth face mask) maximal cardiopulmonary exercise tests (CPETs) on a treadmill following the Bruce protocol. Blood pressure, heart rate, oxygen saturation, exertion and shortness of breath were measured. Descriptive data and physical activity history were collected pretrial; perceptions of wearing face masks and experiential data were gathered immediately following the masked trial. RESULTS: The final sample included 31 adults (age=23.2±3.1 years; 14 women/17 men). Data indicated that wearing a cloth face mask led to a significant reduction in exercise time (-01:39±01:19 min/sec, p<0.001), maximal oxygen consumption (VO2max) (-818±552 mL/min, p<0.001), minute ventilation (-45.2±20.3 L/min), maximal heart rate (-8.4±17.0 beats per minute, p<0.01) and increased dyspnoea (1.7±2.9, p<0.001). Our data also suggest that differences in SpO2 and rating of perceived exertion existed between the different stages of the CPET as participant's exercise intensity increased. No significant differences were found between conditions after the 7-minute recovery period. CONCLUSION: Cloth face masks led to a 14% reduction in exercise time and 29% decrease in VO2max, attributed to perceived discomfort associated with mask-wearing. Compared with no mask, participants reported feeling increasingly short of breath and claustrophobic at higher exercise intensities while wearing a cloth face mask. Coaches, trainers and athletes should consider modifying the frequency, intensity, time and type of exercise when wearing a cloth face mask.

Dietary Polyphenol and Methylsulfonylmethane Supplementation Improves Immune, DAMP Signaling, and Inflammatory Responses During Recovery From All-Out Running Efforts.

Nutritional ingredients with defined mechanisms of action can be useful in the recovery of the body from the physical demands of a habitual training plan. The purpose of this study was to determine the effect of dietary supplementation with optimized curcumin, pomegranate ellagitannins, and MSM (R + MSM) on immune-associated mRNA during early recovery (i.e., up to 8 h post-exercise) following all-out running efforts (5-km, 10-km, and 21.1-km). Subjects (N = 14) were randomized to either a supplement (R + MSM) or a control group using an open label design. The study was completed over a period of 31-day prior to a scheduled half-marathon race. Venous blood samples were collected into PAXgene tubes at baseline, subsequent samples were collected at 2, 4, and 8 h after each running effort. A 574-plex mRNA Immunology Array (NanoString) was measured for each sample and ROSALIND® Advanced Analysis Software was used to examined changes in 31 annotated immune response pathways and specific mRNA changes. The greatest change in immune pathways occurred at 2 h (GSS > 3) followed by 4 h (GSS 2-3) and 8 h (GSS 1-2). R + MSM was associated with an increase in innate immunity (CAMP, LTF, TIRAP, CR1, IL1R1, CXCR1, PDCDILG2, and GNLY) and a blunted/smaller increase in damage-associated molecular pattern (DAMP) signaling/inflammation (TLR4, TLR5, S100A8, S100A9, and IFP35). We also found changes in immune-associated mRNA that have not been previously linked to exercise recovery (SOCS1, SOCS2, MME, CECAM6, MX1, IL-1R2, KLRD1, KLRK1, and LAMP3). Collectively these results demonstrate that supplementation with a combination of optimized curcumin, pomegranate ellagitannins, and methylsulfonylmethane resulted in changes that may improve biological recovery from all-out running efforts.

Identifying nootropic drug targets via large-scale cognitive GWAS and transcriptomics.

Broad-based cognitive deficits are an enduring and disabling symptom for many patients with severe mental illness, and these impairments are inadequately addressed by current medications. While novel drug targets for schizophrenia and depression have emerged from recent large-scale genome-wide association studies (GWAS) of these psychiatric disorders, GWAS of general cognitive ability can suggest potential targets for nootropic drug repurposing. Here, we (1) meta-analyze results from two recent cognitive GWAS to further enhance power for locus discovery; (2) employ several complementary transcriptomic methods to identify genes in these loci that are credibly associated with cognition; and (3) further annotate the resulting genes using multiple chemoinformatic databases to identify "druggable" targets. Using our meta-analytic data set (N = 373,617), we identified 241 independent cognition-associated loci (29 novel), and 76 genes were identified by 2 or more methods of gene identification. Actin and chromatin binding gene sets were identified as novel pathways that could be targeted via drug repurposing. Leveraging our transcriptomic and chemoinformatic databases, we identified 16 putative genes targeted by existing drugs potentially available for cognitive repurposing.

Exercise above the maximal lactate steady state does not elicit a V̇O2 slow component that leads to attainment of V̇O2max.

There is a pervasive belief that the severe-intensity domain is defined as work rates above the power associated with a maximal lactate steady state (MLSS) and by a oxygen uptake (V̇O2) response that demonstrates a rapid increase (primary phase) followed by a slower increase (slow component), which leads to maximal oxygen uptake (V̇O2max) if exercise is continued long enough. Fifteen university students performed 5 to 7 tests to calculate power at MLSS (154 ± 29 W). The tests included 30 min of exercise at each of 3 work rates: (i) below (-2 ± 1 W) power at MLSS, (ii) above (+4 ± 1 W) the power at MLSS, and (iii) well above (+19 ± 8 W) power at MLSS. The V̇O2 response in each test was described using mathematical modeling. Contrary to expectation, the response at the supra-MLSS work rates had not 2, but 3, distinct phases: the primary phase and the slow component, plus a "delayed" third phase, which emerged after ∼15 min. V̇O2max was not attained at supra-MLSS work rates. These results challenge commonly held beliefs about definitions and descriptions of exercise intensity domains. Novelty: The V̇O2 response at work rates that are too high to sustain a lactate steady state but not high enough to elicit V̇O2max features not 2, but 3, distinct phases. There is no consensus on whether intensity domains should be defined by their boundaries or by the responses they engender.

The effect of time of day and chronotype on the relationships between mood state and performance in a Wingate test.

The purpose of this study was to investigate the effects of time-of-day and morning vs. evening chronotype on the relationships between mood state and performance of extreme intensity cycling exercise. A quasi-experimental between-groups design was used to test the hypothesis that there would be an effect of time-of-day on mood state and physical performance, that mood state and physical performance would be interrelated, and that the relationships would be influenced by participants' morning vs. evening chronotype. From 74 university students who volunteered, 7 were identified as morning types (M-types) and 7 as evening types (E-types). They completed the Profile of Mood States (POMS) questionnaire and performed a 30 s Wingate test on three different days, once at 08h00, once at 14h00, and once at 20h00. The main performance measure, work done in the Wingate test, increased across the day (16.4 ± 4.8 kJ < 17.0 ± 5.0 kJ < 17.6 ± 5.2 kJ; p < .01). For the M-types, individual changes in performance from the morning to the afternoon were correlated with individual changes in the POMS score for vigor (r = 0.81; p = .03) and changes in performance from the afternoon to the evening were correlated with individual changes in fatigue (r = - 0.85, p = .02). For the E-types, the opposite was true, as morning-to-afternoon changes in performance were correlated with individual changes in fatigue (r = - 0.70, p = .08) and afternoon-to-evening changes in performance were correlated with individual changes in vigor (r = 0.78, p = .04). Results demonstrate a time-of-day effect on morning vs. evening chronotype-dependent relationships between mood state and cycling performance.

The Increase in Oxygen Demand During Severe Intensity Exercise Must be Included in Calculation of Oxygen Deficit.

A contentious element in the traditional method of calculating accumulated oxygen deficit (AOD) is the assumption that the oxygen demand remains constant throughout a bout of exercise. The purpose of this study was to investigate the appropriateness of this assumption. Twelve women and eight men volunteered for the study and completed cycle ergometer tests that resulted in exhaustion after ~4 min and ~8 min. In each test, AOD was calculated by subtracting accumulated oxygen uptake (in mL·kg-1) from estimated total oxygen cost (in mL·kg-1), which was estimating two ways: (i) assuming that oxygen demand (in mL·kg-1·min-1) increases over the course of the exercise bout and (ii) assuming it remains constant. Values for AOD in the 4-min and 8-min tests were expected to be the same (maximal). Mean values for AOD in the 4-min and 8-min tests were similar (79.1 ± 7.6 mL·kg-1 and 79.6 ± 8.3 mL·kg-1) when calculated assuming an increase in oxygen demand, but different (71.0 ± 7.9 mL·kg-1 and 42.5 ± 7.6 mL·kg-1) when the demand was kept constant. These results support the hypothesis that oxygen demand increases during exhaustive severe intensity cycling exercise. This increase must be included in calculation of AOD.

Determining MAOD Using a Single Exhaustive Severe Intensity Test.

Maximal accumulated oxygen deficit (MAOD) provides a measure of anaerobic capacity. However, its measurement is a time-consuming process. The purpose of this study was to evaluate a measure of anaerobic capacity that avoids contentious assumptions and demands of the MAOD method. Twelve women and eight men volunteered for the study and completed cycle ergometer tests that resulted in exhaustion after ~4 min and ~8 min. In each test, anaerobic capacity was determined as (i) the MAOD and (ii) the sum of the phosphocreatine and glycolytic contributions (PCr+glycolysis). MAOD was determined by subtraction of the accumulated oxygen uptake from the total oxygen cost. Phosphocreatine and glycolytic contributions were calculated from post-exercise VO2 and blood lactate responses. MAOD in the 4-min and 8-min tests (79.1 ± 7.6 mL·kg-1 and 79.6 ± 7.4 mL·kg-1) and PCr+glycolysis in these tests (80.0 ± 7.3 mL·kg-1 and 79.0 ± 6.9 mL·kg-1) were correlated (r ≥ 0.91) and not significantly different. These results support the use of postexercise measures to quantify the phosphocreatine and glycolytic contributions and to provide an alternative to MAOD for measurement of anaerobic capacity.

Alcohol After Resistance Exercise Does Not Affect Muscle Power Recovery.

Levitt, DE, Idemudia, NO, Cregar, CM, Duplanty, AA, Hill, DW, and Vingren, JL. Alcohol after resistance exercise does not affect muscle power recovery. J Strength Cond Res 34(7): 1938-1944, 2020-The purpose of this study was to investigate the effect of alcohol consumed after heavy eccentric resistance exercise on measures of muscle power. After familiarization and an initial eccentric exercise bout to control for the "repeated-bout effect," 10 recreationally resistance-trained men completed 2 identical heavy eccentric squat bouts (4 sets of 10 repetitions at 110% of concentric 1-repetition maximum) 1 week apart. Each exercise bout was followed by ingestion of a beverage containing either alcohol (1.09 g ethanol·kg fat-free body mass) or no alcohol (placebo; volume of alcohol replaced with water). Vertical jump (VJ) peak power, VJ peak force, VJ jump height, change-of-direction ability (shuttle run), sprint acceleration (sprint test), and muscle soreness were measured before (PRE), 24 hours after (24H), and 48 hours after (48H) each eccentric exercise bout. Although the exercise bout resulted in significantly (p ≤ 0.05) decreased VJ peak power at 24H, significantly decreased VJ jump height at 24H, and significantly increased muscle soreness at 24H and 48H, consuming alcohol after the exercise bout did not affect any of the performance outcome measures. When consumed after a non-novel heavy eccentric resistance exercise bout, alcohol did not affect soreness or recovery of muscular power. Practitioners can use this information to advise their athletes with regard to responsible alcohol use after non-novel exercise. Although short-term anaerobic performance does not seem compromised as a result of acute postexercise alcohol ingestion, practitioners and athletes should be aware of potential long-term effects of such alcohol use.