Is a Four-Week Ketogenic Diet an Effective Nutritional Strategy in CrossFit-Trained Female and Male Athletes?

This single-arm interventional study examined the effect of a 4-week ketogenic diet (KD) on aerobic capacity and discipline-specific performance in female (n = 11) and male (n = 11) CrossFit-trained athletes. The participants performed incremental cycling (ICT) and Fight Gone Bad (FGB) tests after consuming a customary diet and a KD. Pre- and post-ICT exercise blood samples were also analysed. Consuming a KD had a slight impact on aerobic capacity and no relevant effect on CrossFit-specific performance. In females, consuming a KD led to an 10.4% decrease in peak oxygen uptake during the ICT (p = 0.027) and resulted in certain alterations in haematological parameters (haemoglobin (HGB), mean corpuscular HGB, and mean corpuscular HGB concentration). Furthermore, in males, alanine aminotransferase activity increased with a simultaneous improvement in the post-ICT blood acid–base balance after consuming a KD. The pre-exercise bilirubin concentration was also elevated in the entire group after consuming a KD. In conclusion, female CrossFit-trained athletes seem to be prone to aerobic performance decrements and increased risk of developing haematological disturbances when consuming a KD. In males who consumed a KD, there was an undesirable alanine aminotransferase elevation and a small tendency towards improved acid–base status. Moreover, consuming a KD had no effect on discipline-specific performance in CrossFit-trained athletes.

Download Full-text

Post-exercise Supplementation of Sodium Bicarbonate Improves Acid Base Balance Recovery and Subsequent High-Intensity Boxing Specific Performance

Frontiers in Nutrition ◽

10.3389/fnut.2019.00155 ◽

2019 ◽

Vol 6 ◽

Author(s):

Lewis A. Gough ◽

Steven Rimmer ◽

S. Andy Sparks ◽

Lars R. McNaughton ◽

Matthew F. Higgins

Keyword(s):

Sodium Bicarbonate ◽

High Intensity ◽

Acid Base Balance ◽

Acid Base ◽

Post Exercise ◽

Balance Recovery ◽

Specific Performance ◽

Base Balance

Download Full-text

Phenome-wide association of 1809 phenotypes and COVID-19 disease progression in the Veterans Health Administration Million Veteran Program

PLoS ONE ◽

10.1371/journal.pone.0251651 ◽

2021 ◽

Vol 16 (5) ◽

pp. e0251651

Author(s):

Rebecca J. Song ◽

Yuk-Lam Ho ◽

Petra Schubert ◽

Yojin Park ◽

Daniel Posner ◽

...

Keyword(s):

Risk Factors ◽

Disease Progression ◽

Bacterial Infections ◽

Older Age ◽

Health Administration ◽

Acid Base Balance ◽

Acid Base ◽

Increased Risk ◽

Base Balance ◽

Balance Disorder

Background The risk factors associated with the stages of Coronavirus Disease-2019 (COVID-19) disease progression are not well known. We aim to identify risk factors specific to each state of COVID-19 progression from SARS-CoV-2 infection through death. Methods and results We included 648,202 participants from the Veteran Affairs Million Veteran Program (2011-). We identified characteristics and 1,809 ICD code-based phenotypes from the electronic health record. We used logistic regression to examine the association of age, sex, body mass index (BMI), race, and prevalent phenotypes to the stages of COVID-19 disease progression: infection, hospitalization, intensive care unit (ICU) admission, and 30-day mortality (separate models for each). Models were adjusted for age, sex, race, ethnicity, number of visit months and ICD codes, state infection rate and controlled for multiple testing using false discovery rate (≤0.1). As of August 10, 2020, 5,929 individuals were SARS-CoV-2 positive and among those, 1,463 (25%) were hospitalized, 579 (10%) were in ICU, and 398 (7%) died. We observed a lower risk in women vs. men for ICU and mortality (Odds Ratio (95% CI): 0.48 (0.30–0.76) and 0.59 (0.31–1.15), respectively) and a higher risk in Black vs. Other race patients for hospitalization and ICU (OR (95%CI): 1.53 (1.32–1.77) and 1.63 (1.32–2.02), respectively). We observed an increased risk of all COVID-19 disease states with older age and BMI ≥35 vs. 20–24 kg/m2. Renal failure, respiratory failure, morbid obesity, acid-base balance disorder, white blood cell diseases, hydronephrosis and bacterial infections were associated with an increased risk of ICU admissions; sepsis, chronic skin ulcers, acid-base balance disorder and acidosis were associated with mortality. Conclusions Older age, higher BMI, males and patients with a history of respiratory, kidney, bacterial or metabolic comorbidities experienced greater COVID-19 severity. Future studies to investigate the underlying mechanisms associated with these phenotype clusters and COVID-19 are warranted.

Download Full-text

The effects of intermittent normobaric hypoxic training duration on aerobic performance and acid-base balance in blood

Exercise Science ◽

10.15857/ksep.2010.19.2.175 ◽

2010 ◽

Vol 19 (2) ◽

pp. 175-188 ◽

Cited By ~ 2

Author(s):

Sang-Seok Nam ◽

Sub Sunoo

Keyword(s):

Aerobic Performance ◽

Acid Base Balance ◽

Acid Base ◽

Hypoxic Training ◽

Base Balance

Download Full-text

Effects of Short-Term Phosphate Loading on Aerobic Capacity under Acute Hypoxia in Cyclists: A Randomized, Placebo-Controlled, Crossover Study

Nutrients ◽

10.3390/nu14020236 ◽

2022 ◽

Vol 14 (2) ◽

pp. 236

Author(s):

Kamila Płoszczyca ◽

Małgorzata Chalimoniuk ◽

Iwona Przybylska ◽

Miłosz Czuba

Keyword(s):

Crossover Study ◽

Aerobic Capacity ◽

Acute Hypoxia ◽

Hypoxia Inducible Factor ◽

Oxygen Affinity ◽

Individual Variability ◽

Aerobic Performance ◽

Acid Base Balance ◽

Phosphate Loading ◽

2,3 Dpg

The aim of this study was to evaluate the effects of sodium phosphate (SP) supplementation on aerobic capacity in hypoxia. Twenty-four trained male cyclists received SP (50 mg·kg−1 of FFM/day) or placebo for six days in a randomized, crossover study, with a three-week washout period between supplementation phases. Before and after each supplementation phase, the subjects performed an incremental exercise test to exhaustion in hypoxia (FiO2 = 16%). Additionally, the levels of 2,3-diphosphoglycerate (2,3-DPG), hypoxia-inducible factor 1 alpha (HIF-1α), inorganic phosphate (Pi), calcium (Ca), parathyroid hormone (PTH) and acid-base balance were determined. The results showed that phosphate loading significantly increased the Pi level by 9.0%, whereas 2,3-DPG levels, hemoglobin oxygen affinity, buffering capacity and myocardial efficiency remained unchanged. The aerobic capacity in hypoxia was not improved following SP. Additionally, our data revealed high inter-individual variability in response to SP. Therefore, the participants were grouped as Responders and Non-Responders. In the Responders, a significant increase in aerobic performance in the range of 3–5% was observed. In conclusion, SP supplementation is not an ergogenic aid for aerobic capacity in hypoxia. However, in certain individuals, some benefits can be expected, but mainly in athletes with less training-induced central and/or peripheral adaptation.

Download Full-text

Higher Dietary Acidity is Associated with Lower Bone Mineral Density in Postmenopausal Iranian Women, Independent of Dietary Calcium Intake

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000207 ◽

2014 ◽

Vol 84 (3-4) ◽

pp. 0206-0217 ◽

Cited By ~ 8

Author(s):

Seyedeh-Elaheh Shariati-Bafghi ◽

Elaheh Nosrat-Mirshekarlou ◽

Mohsen Karamati ◽

Bahram Rashidkhani

Keyword(s):

Calcium Intake ◽

Dietary Calcium ◽

Dietary Calcium Intake ◽

Dietary Intakes ◽

Iranian Women ◽

Acid Base Balance ◽

Mineral Density ◽

Acid Base ◽

Base Balance ◽

Dietary Acid

Findings of studies on the link between dietary acid-base balance and bone mass are relatively mixed. We examined the association between dietary acid-base balance and bone mineral density (BMD) in a sample of Iranian women, hypothesizing that a higher dietary acidity would be inversely associated with BMD, even when dietary calcium intake is adequate. In this cross-sectional study, lumbar spine and femoral neck BMDs of 151 postmenopausal women aged 50 - 85 years were measured using dual-energy x-ray absorptiometry. Dietary intakes were assessed using a validated food frequency questionnaire. Renal net acid excretion (RNAE), an estimate of acid-base balance, was then calculated indirectly from the diet using the formulae of Remer (based on dietary intakes of protein, phosphorus, potassium, and magnesium; RNAERemer) and Frassetto (based on dietary intakes of protein and potassium; RNAEFrassetto), and was energy adjusted by the residual method. After adjusting for potential confounders, multivariable adjusted means of the lumbar spine BMD of women in the highest tertiles of RNAERemer and RNAEFrassetto were significantly lower than those in the lowest tertiles (for RNAERemer: mean difference -0.084 g/cm2; P=0.007 and for RNAEFrassetto: mean difference - 0.088 g/cm2; P=0.004). Similar results were observed in a subgroup analysis of subjects with dietary calcium intake of >800 mg/day. In conclusion, a higher RNAE (i. e. more dietary acidity), which is associated with greater intake of acid-generating foods and lower intake of alkali-generating foods, may be involved in deteriorating the bone health of postmenopausal Iranian women, even in the context of adequate dietary calcium intake.

Download Full-text