The Effect of Wearing a Treadmill Harness on Cardiopulmonary Function and Blood Lactate

The aim of this study was to analyze the influence of two velocities of execution relative to blood lactate concentration in strength training exercise until the momentary concentric failure. Fifteen men (29.1 ± 5.9 years), trained, participated in the experiment. The volunteers performed three bench press sessions, with an interval of 48 hours between them. At the first session, individuals determined loads through the 10-12 RMs test. In the following two sessions, three series with 90 seconds of interval were performed, in the second session slow execution speed (cadence 3030) and later in the third session fast speed (cadence 1010). For statistical analysis, the Student-T test was used for an independent sample study and considered the value of probability (p) ≤ 0.05 statistically significant. By comparing the number of repetitions and time under tension of the two runs, all series compared to the first presented significant reductions (p < 0.05). The total work volume was higher with the fast speed (p < 0.05). The study revealed that rapid velocities (cadence 1010) present a higher concentration of blood lactate when compared to slow runs (cadence 3030). The blood lactate concentration, in maximum repetitions, is affected by the speed of execution.Keywords: resistance training, cadence, blood lactate.

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Caffeine supplementation for 4-day, followed by acute ingestion, did not impact triathlete output power after submaximal intensity exercise

Revista Brasileira de Fisiologia do Exercício ◽

10.33233/rbfe.v18i3.3230 ◽

2019 ◽

Vol 18 (3) ◽

pp. 118

Author(s):

Anderson Pontes Morales ◽

Felipe Sampaio-Jorge ◽

Thiago Barth ◽

Alessandra Alegre De Matos ◽

Luiz Felipe Da Cruz Rangel ◽

...

Keyword(s):

Blood Lactate ◽

Output Power ◽

Body Mass ◽

Effect Size ◽

Power Output ◽

Anaerobic Power ◽

Lactate Concentration ◽

Wingate Test ◽

Large Effect Size ◽

Acute Ingestion

Introduction: The aim of this study was to test the hypothesis that caffeine supplementation (6 mg·kg-1 body mass) for 4-days, followed by acute intake, would impact five male triathletes output power after performed submaximal intensity exercise. Methods: This was a randomized, double-blind, placebo-controlled crossover study, placebo (4-day) - placebo (acute) PP, placebo (4-days) -caffeine (acute) PC, and caffeine (4-day) - caffeine (acute) CC. Participants abstained from dietary caffeine sources for 4 days and ingested capsules containing either placebo or caffeine (6 mg.kg-1 body mass day in one absorption). The acute trials the capsules containing placebo or caffeine (6 mg.kg-1 body mass day in one absorption) were ingested 60min before completing exercise in a treadmill for 40min (80% VO2max) and to perform the Wingate test. Results: Blood lactate was determined before, 60min after ingestion, and immediately after the exercise on the treadmill, the Wingate test, and after the recovery (10-min). CC and PC trials did not change the cardiopulmonary variables (P>0.05) and the anaerobic power variables (peak/mean power output and fatigue index) (P>0.05). The PC trial compared with PP promoted improvements in the curve power output in 2 sec by 31.19% (large effect-size d = 1.08; P<0.05) and 3 sec by 20% (large effect-size d = 1.19; P<0.05). A 10min recovery was not sufficient to reduce blood lactate concentration in the PC trial compared with PP (PC, 13.73±2.66 vs. PP, 10.26±1.60 mmol.L-1; P<0.05, respectively) (P<0.05). Conclusion: In conclusion, these results indicate that caffeine supplementation (6 mg·kg-1 body mass) for 4 days, followed by acute ingestion, did not impact the triathletes output power after performed submaximal intensity exercise. Nutritional interventions may help researchers and athletes to adapt strategies for manipulating caffeine use.Key-words: caffeine metabolism, Wingate test, blood lactate, performance.

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Efficacy of Near-Infrared Spectrometry for Monitoring the Cerebral Effects of Severe Dilutional Anemia

The Heart Surgery Forum ◽

10.1532/hsf98.2013293 ◽

2014 ◽

Vol 17 (3) ◽

pp. 154 ◽

Cited By ~ 10

Author(s):

Arıtürk Cem ◽

Ustalar Serpil ◽

Toraman Fevzi ◽

Ökten Murat ◽

Güllü Ümit ◽

...

Keyword(s):

Blood Flow ◽

Cardiac Surgery ◽

Blood Lactate ◽

Near Infrared ◽

Bypass Graft ◽

Blood Gas Analysis ◽

Gas Analysis ◽

Infrared Spectrometry ◽

Control Group ◽

Near Infrared Spectrometry

Introduction: Clear guidelines for red cell transfusion during cardiac surgery have not yet been established. The current focus on blood conservation during cardiac surgery has increased the urgency to determine the minimum safe hematocrit for these patients. The aim of this study was to determine whether monitoring of cerebral regional oxygen saturation (rSO2) via near-infrared spectrometry (NIRS) is effective for assessing the cerebral effects of severe dilutional anemia during elective coronary arterial bypass graft surgery (CABG).Methods: The prospective observational study involved patients who underwent cerebral rSO2 monitoring by NIRS during elective isolated first-time CABG: an anemic group (N=15) (minimum Hemoglobin (Hb) N=15) (Hb >8 g/dL during CPB). Mean arterial pressure (MAP), pump blood flow, blood lactate level, pCO2, pO2 at five time points and cross-clamp time, extracorporeal circulation time were recorded for each patient. Group results statistically were compared.Results: The anemic group had significantly lower mean preoperative Hb than the control group (10.3 mg/dL versus 14.2 mg/dL; P = .001). The lowest Hb levels were observed in the hypothermic period of CPB in the anemic group. None of the controls exhibited a >20% decrease in cerebral rSO2. Eleven (73.3%) of the anemic patients required an increase in pump blood flow to raise their cerebral rSO2.Conclusions: In this study, the changes in cerebral rSO2 in the patients with low Hb were within acceptable limits, and this was in concordance with the blood lactate levels and blood-gas analysis. It can be suggested that NIRS monitoring of cerebral rSO2 can assist in decision making related to blood transfusion and dilutional anemia during CPB.

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