The Effects of an Acute “Train-Low” Nutritional Protocol on Markers of Recovery Optimization in Endurance-Trained Male Athletes

Author(s):  
Isabella Russo ◽  
Paul A. Della Gatta ◽  
Andrew Garnham ◽  
Judi Porter ◽  
Louise M. Burke ◽  
...  

Purpose: This study aimed to determine the effects of an acute “train-low” nutritional protocol on markers of recovery optimization compared to standard recovery nutrition protocol. Methods: After completing a 2-hour high-intensity interval running protocol, 8 male endurance athletes consumed a standard dairy milk recovery beverage (CHO; 1.2 g/kg body mass [BM] of carbohydrate and 0.4 g/kg BM of protein) and a low-carbohydrate (L-CHO; isovolumetric with 0.35 g/kg BM of carbohydrate and 0.5 g/kg BM of protein) dairy milk beverage in a double-blind randomized crossover design. Venous blood and breath samples, nude BM, body water, and gastrointestinal symptom measurements were collected preexercise and during recovery. Muscle biopsy was performed at 0 hour and 2 hours of recovery. Participants returned to the laboratory the following morning to measure energy substrate oxidation and perform a 1-hour distance test. Results: The exercise protocol resulted in depletion of muscle glycogen stores (250 mmol/kg dry weight) and mild body-water losses (BM loss = 1.8%). Neither recovery beverage replenished muscle glycogen stores (279 mmol/kg dry weight) or prevented a decrease in bacterially stimulated neutrophil function (−21%). Both recovery beverages increased phosphorylation of mTORSer2448 (main effect of time = P < .001) and returned hydration status to baseline. A greater fold increase in p-GSK-3βSer9/total-GSK-3β occurred on CHO (P = .012). Blood glucose (P = .005) and insulin (P = .012) responses were significantly greater on CHO (618 mmol/L per 2 h and 3507 μIU/mL per 2 h, respectively) compared to L-CHO (559 mmol/L per 2 h and 1147 μIU/mL per 2 h, respectively). Rates of total fat oxidation were greater on CHO, but performance was not affected. Conclusion: A lower-carbohydrate recovery beverage consumed after exercise in a “train-low” nutritional protocol does not negatively impact recovery optimization outcomes.

1990 ◽  
Vol 69 (4) ◽  
pp. 1397-1401 ◽  
Author(s):  
W. F. Brechue ◽  
J. M. Stager ◽  
H. C. Lukaski

Acetazolamide (ACZ), a potent carbonic anhydrase inhibitor, is a known diuretic and causal agent in metabolic acidosis. Its diuretic qualities are well established with respect to urine flow and electrolyte excretion. However, the impact of ACZ on body hydration status has not been adequately quantified. Thus, to establish the influence of ACZ treatment on body water, nine healthy males were evaluated for hydration status after clinically prescribed doses of ACZ. The drug was administered in three 250-mg oral doses 14, 8, and 2 h before determination of body water compartments. ACZ led to a significant 1.7-liter reduction in total body water (3.4%). A significant reduction in extracellular water of 3.3 liters is partitioned as the loss of total body water and a significant increase in intracellular water (1.6 liters). Venous blood pH and plasma HCO3- were significantly reduced 0.09 units and 5.9 mM, respectively, with ACZ. Plasma protein concentration was increased, but plasma osmolality did not change. Plasma Na+, K+, and Cl- concentrations were not different with ACZ, but total electrolyte content was significantly decreased 45.2, 1.17, and 44.1 meq, respectively, for all three. Urine K+, HCO3-, flow, and pH were elevated after ACZ treatment, whereas Na+ and Cl- were the same as placebo levels. In conclusion, acute clinical doses of ACZ reduce body fluid compartments, leading to a moderate isosmotic hypovolemia with an intracellular volume expansion as well as metabolic acidosis.


1997 ◽  
Vol 83 (5) ◽  
pp. 1482-1485 ◽  
Author(s):  
Sven Asp ◽  
Thomas Rohde ◽  
Erik A. Richter

Asp, Sven, Thomas Rohde, and Erik A. Richter. Impaired muscle glycogen resynthesis after a marathon is not caused by decreased muscle GLUT-4 content. J. Appl. Physiol. 83(5): 1482–1485, 1997.—Our purpose was to investigate whether the slow rate of muscle glycogen resynthesis after a competitive marathon is associated with a decrease in the total muscle content of the muscle glucose transporter (GLUT-4). Seven well-trained marathon runners participated in the study, and muscle biopsies were obtained from the lateral head of the gastrocnemius muscle before, immediately after, and 1, 2, and 7 days after the marathon, as were venous blood samples. Muscle GLUT-4 content was unaltered over the experimental period. Muscle glycogen concentration was 758 ± 53 mmol/kg dry weight before the marathon and decreased to 148 ± 39 mmol/kg dry weight immediately afterward. Despite a carbohydrate-rich diet (containing at least 7 g carbohydrate ⋅ kg body mass−1 ⋅ day−1), the muscle glycogen concentration remained 30% lower than before-race values 2 days after the race, whereas it had returned to before-race levels 7 days after the race. We conclude that the total GLUT-4 protein content is unaltered in the lateral gastrocnemius after a competitive marathon and that the slow recovery of muscle glycogen after the race apparently involves factors other than changes in the total content of this protein.


2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Gertrud Schuster ◽  
Chidchamai Kewcharoenwong ◽  
Maxwell Barffour ◽  
Guy-Marino Hinnouho ◽  
Janet Peerson ◽  
...  

Abstract Objectives Determine if children (6 to 23 mo) who received daily preventive zinc (PZ; 7 mg/d), daily high-zinc, low-iron micronutrient powder (MNP; 10 mg/d zinc, 6 mg/d iron) or therapeutic zinc during episodes of diarrhea (TZ; 20 mg/d for 10 d per episode) have improved markers of innate and adaptive immune function, compared to placebo (PL). Methods Rural Laotian children were recruited into a double-blind, randomized, controlled intervention trial for 9 mo. Venous blood was collected at baseline (BL) and endline (EL) for analysis. Primary outcomes included T-cell subsets (naïve and memory CD4, CD8, Tregs) measured by flow cytometry and production of T-cell cytokines (IL-2, IL-10, IL-13, IL-17A, INF-γ) and LPS-induced cytokines (IL-1β, IL-6, IL-10, TNF-α by whole blood cultures. Blood leukocytes (including lymphocytes, neutrophils, monocytes and eosinophils) were measured as secondary outcome variables. Group means at EL were compared by analysis of covariance (controlling for BL values of the outcome, sex, child age, district, month of enrollment and plasma zinc concentration). If an interaction with BL plasma zinc (above/below median) was observed, group means were compared separately in children above and below the median. Results Mean BL plasma zinc in all children (N = 574) was 0.55 ± 0.12 mg/L. No significant group differences were seen at EL in the primary outcomes. For secondary outcomes, the counts (^103/μL) of lymphocytes from the PZ group (5.02 ± 0.16) were significantly lower than the PL group (5.64 ± 0.16; P = 0.032). The EL counts (^103/μL) of from the PZ group (0.144 ± 0.026) were significantly lower than in the PL (0.279 ± 0.048; P = 0.036) and TZ (0.285 ± 0.047; P = 0.025) groups among children with baseline zinc below the median. Conclusions Primary outcomes (T-cell subsets, and cytokine production) were not affected by the zinc intervention. Lymphocyte and eosinophil concentrations may be affected by zinc treatment but this result requires confirmation. Funding Sources ARS Project 2032-53000-001-00-D, Mathile Institute for the Advancement of Human Nutrition.


2004 ◽  
Vol 14 (4) ◽  
pp. 419-429 ◽  
Author(s):  
Kelly A. Fiala ◽  
Douglas J. Casa ◽  
Melissa W. Roti

The purpose of this study was to assess the influence of rehydration with a caffeinated beverage during non exercise periods on hydration status throughout consecutive practices in the heat. Ten (7 women, 3 men) partially heat-acclimated athletes (age 24 ± ly, body fat 19.2 ± 2%, weight 68.4 ± 4.0 kg, height 170 ± 3 cm) completed 3 successive days of 2-a-day practices (2 h/ practice, 4 h/d) in mild heat (WBGT = 23 °C). The 2 trials (double-blind, random, cross-over design) included; 1) caffeine (CAF) rehydrated with Coca-Cola® and 2) caffeine-free (CF) rehydrated with Caffeine-Free Coca-Cola®. Urine and psychological measures were determined before and after each 2-h practice. A significant difference was found for urine color for the post-AM time point, F = 5.526, P = 0.031. No differences were found among other variables (P > 0.05). In summary, there is little evidence to suggest that the use of beverages containing caffeine during non exercise might hinder hydration status.


1985 ◽  
Vol 65 (3) ◽  
pp. 745-751
Author(s):  
N. R. DEUEL ◽  
L. M. LAWRENCE ◽  
W. W. ALBERT

Sodium bicarbonate or a commercial vitamin-mineral mixture was included at the 1% level (air-dry weight) in the diets of 16 yearling horses over a 140-day period in a 2 × 2 factorial design. Feed additives resulted in a pH range from 5.78 to 7.87 in the concentrate portion of the diets. Feces, urine and venous blood were collected 24 h after feeding the concentrate. Average daily gain, respiration rate, venous pCO2 and pO2, as well as serum K, Cl, Ca, P, urea N and protein levels were unaffected by treatment. Horses receiving the vitamin-mineral supplement had higher serum Na and lower serum glucose concentrations than horses not receiving the supplement. Horses receiving sodium bicarbonate had a higher urine pH, lower fecal pH, higher packed cell volume, lower blood pH and lower serum glucose concentrations at 24 h after a meal than horses not receiving the buffer. Key words: Horse, sodium bicarbonate, dietary supplements, hematology


1988 ◽  
Vol 65 (4) ◽  
pp. 1553-1555 ◽  
Author(s):  
M. Hargreaves ◽  
C. A. Briggs

Five male cyclists were studied during 2 h of cycle ergometer exercise (70% VO2 max) on two occasions to examine the effect of carbohydrate ingestion on muscle glycogen utilization. In the experimental trial (CHO) subjects ingested 250 ml of a glucose polymer solution containing 30 g of carbohydrate at 0, 30, 60, and 90 min of exercise; in the control trial (CON) they received an equal volume of a sweet placebo. No differences between trials were seen in O2 uptake or heart rate during exercise. Venous blood glucose was similar before exercise in both trials, but, on average, was higher during exercise in CHO [5.2 +/- 0.2 (SE) mmol/l] compared with CON (4.8 +/- 0.1, P less than 0.05). Plasma insulin levels were similar in both trials. Muscle glycogen levels were also similar in CHO and CON both before and after exercise; accordingly, there was no difference between trials in the amount of glycogen used during the 2 h of exercise (CHO = 62.8 +/- 10.1 mmol/kg wet wt, CON = 56.9 +/- 10.1). The results of this study indicate that carbohydrate ingestion does not influence the utilization of muscle glycogen during prolonged strenuous exercise.


2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Varvara Askiti ◽  
Georgia Malakasioti ◽  
George Servos ◽  
Georgia Grigoriadou ◽  
Andromachi Mitsioni

Abstract Background and Aims The determination of dry weight (DW) in children on chronic hemodialysis (HD) remains problematic. No method has been shown superior for DW assessment in the few pediatric studies exploring the utility of inferior vena cava expiratory and inspiratory diameter diameter (IVCDe, IVCDi) and BIS against clinical criteria. We aimed to compare the performance of IVCD, BIS and clinical judgement in DW prediction in hemodialyzed children. Method IVCD and BIS were measured serially pre and post the midweek HD session. IVCDi, IVCDe and IVC contractility index (IVCCI) associations with: (1) BIS estimated (BIS-relOH) and (2) clinically assessed hydration status (OHc) based on deviation from DW were explored. The interpretation of IVC measurements was based on previously published pediatric reference values. The level of agreement between the three tools in fluid overload recognition was studied. Results Fifty-two sets of measurements were undertaken in 13 patients (median age 11 years). OHc and BIS-relOH were positively associated to each other (r=0,5, p&lt;0,05) and to IVCDi (r=0,4, r=0,5, p&lt;0,05) and IVCDe (r=0,4, r=0,6, p&lt;0,05). A negative association between IVCCI and relOH-BIS was observed (r= -0,4, p&lt;0,05). There was a poor agreement between the three methods in identification of fluid overload; out of 28 clinically overloaded patients, BIS identified only 7 whereas IVCD none (Cohen’s k &lt;0). Conclusion IVCD measurements alone are not reliable for accurate fluid status prediction in hemodialyzed children as they seem to underestimate fluid overload compared to BIS and clinical criteria. Further studies are warranted to explore the applicability of new technologies for DW assessment of dialysis patients.


1997 ◽  
Vol 20 (7) ◽  
pp. 371-374 ◽  
Author(s):  
B. Oe ◽  
W.M. De Fijter ◽  
C.W.H. De Fijter ◽  
B. Straver ◽  
P.L. Oe ◽  
...  

The purpose of the present study was to investigate whether total body bioelectrical impedance analysis (BIA) could be appropriate to assess normohydration (i.e. dry weight) in hemodialysis patients. This study is warranted, because the simultaneous assessment of both hydration and nutritional status by BIA requires the presence of a situation of normohydration in order to guarantee valid conclusions about the nutritional analysis. Segmental bioelectrical impedance was performed to classify patients according to their hydration status. BIA measurements revealed significant differences in TBW, ECW and ICW/ECW between three hydration subgroups (under-, normo-, and overhydration), whereas ICW was similar. Therefore, TBW, ECW and ICW/ECW appear appropriate variables to assess hydration status in patients on hemodialysis. Hemodialysis diminished ECW significantly, whereas ICW did not change, suggesting that a decrease of ECW explains the fluid loss during hemodialysis.


Nutrients ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 565 ◽  
Author(s):  
Ana Isabel Laja García ◽  
Maria de Lourdes Samaniego-Vaesken ◽  
Teresa Partearroyo ◽  
Gregorio Varela-Moreiras

The achievement of adequate hydration status is essential for mental and physical performance and for health in general, especially in children and adolescents. Nevertheless, little is known about hydration status of this population, mainly due to the limited availability of research tools; thus, the objective of the current study was to adapt and validate our hydration status questionnaire in a Spanish adolescent-young population. The questionnaire was validated against important hydration markers: urine colour, urine specific gravity, haemoglobin, haematocrit and total body water and involved 128 subjects aged between 12–17 years. Water intake was also estimated through a three-day dietary record and physical activity was assessed through accelerometers. Participants completed the questionnaire twice. Water balance and water intake were correlated with urine specific gravity and with total body water content. Water intake obtained by the questionnaire was correlated with results from the three-day dietary record. The intraclass correlation coefficient indicated moderate concordance between both recordings and the Cronbach’s alpha revealed high consistency. The Bland and Altman method indicated that the limits of agreement were acceptable to reveal the reliability of the estimated measures. In conclusion, this is the first time that a questionnaire is valid and reliable to estimate hydration status of adolescent-young populations.


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