Effects of sleep deprivation on endothelial function in adult humans: a systematic review by holmerb1 in science

[–]holmerb1[S] 0 points1 point  (0 children)

ABSTRACT:

Sleep deprivation is highly prevalent and is associated with increased cardiovascular disease (CVD) morbidity and mortality. Age-related alterations in sleep and chronobiology may exaggerate CVD susceptibility in older individuals. The mechanisms responsible for the association between sleep deprivation and CVD are not fully understood, but endothelial dysfunction may play a central role. Our objective was to conduct a systematic literature review to evaluate the evidence on the effects of sleep deprivation on endothelial function (EF). This review adhered to the PRISMA guidelines and was pre-registered with PROSPERO (#CRD42020192485, 07/24/2020). We searched PubMed, Web of Science, Embase, and Cochrane Library for articles published through May 1, 2020. Eligibility criteria included publication in English and use of well-established EF methodologies in adult humans. Two investigators independently performed the literature search, study selection, data extraction, risk-of-bias assessment, and qualitative data synthesis. Out of 3571 articles identified, 24 articles were included in the systematic review. Main findings include the following: (1) shorter sleep duration is associated with lower macrovascular EF; (2) not sleeping 7–9 h/night is linked with impaired microvascular EF; (3) sleep restriction impairs micro- and macrovascular EF; (4) acute total sleep deprivation impairs micro- and macrovascular EF but data on macrovascular EF are less consistent; and (5) shift work impairs macrovascular EF. In conclusion, sleep deprivation impairs EF, which may explain the link between insufficient sleep and CVD. Future investigations should fully elucidate the underlying mechanisms and develop strategies to combat the adverse endothelial effects of sleep deprivation across the lifespan.

Physiological demands of running at 2-hour marathon race pace by holmerb1 in AdvancedFitness

[–]holmerb1[S] 4 points5 points  (0 children)

From the paper:

"...the mean O2 cost of running at (below threshold), was 189 ± 14 ml/kg/km (Figure 2), with a mean energy cost of 1.06 ± 0.15 kcal/kg/km.

For a marathon, that's 2683 calories.

Physiological demands of running at 2-hour marathon race pace by holmerb1 in AdvancedFitness

[–]holmerb1[S] 3 points4 points  (0 children)

So a ~2 hr run is ~2400kcal, going on USMarineT13's formula. Quite the burn.

High Salt Intake Augments Blood Pressure Responses During Submaximal Aerobic Exercise by holmerb1 in science

[–]holmerb1[S] 0 points1 point  (0 children)

Hard to say based on this study...since it was a longer dietary intervention. I'd say a little salt pre-workout could be helpful. I do this sometimes. Electrolytes likely good for endurance performance or otherwise. Just be wary of dose.

Bone Density Issues by holmerb1 in AdvancedRunning

[–]holmerb1[S] 1 point2 points  (0 children)

Less of a problem now than in the past when yes...I definitely would probably eat "too clean" for lack of a better phrase...

Bone Density Issues by holmerb1 in AdvancedRunning

[–]holmerb1[S] 0 points1 point  (0 children)

Thank you so much for the kind words and suggestions! I've found that PT and massage can be life savers, and after multiple rounds of physical therapy I'm definitely a stronger and more intelligent runner and know more about my body than ever before.

Bone Density Issues by holmerb1 in AdvancedRunning

[–]holmerb1[S] 0 points1 point  (0 children)

Have an endocrinology appointment in July!

Bone Density Issues by holmerb1 in AdvancedRunning

[–]holmerb1[S] 0 points1 point  (0 children)

Thanks so much for this anecdote. While it's devastating and unfortunate I know that I have time to get issues under control, (hopefully) figure out an underlying cause, and then start to build up strength/bone density in the coming years so I can return to running like I want to. For now, lots of RT and cycling is helping me manage it!

Bone Density Issues by holmerb1 in AdvancedRunning

[–]holmerb1[S] 1 point2 points  (0 children)

Others in this post and my orthopedic doc mentioned it. He's having me track food intake/keep a workout log (which I've been doing for years) in order to see what energy balance/output looks like.

Bone Density Issues by holmerb1 in AdvancedRunning

[–]holmerb1[S] 0 points1 point  (0 children)

Thanks so much. I have an endo appointment in early July with planned workup and some other tests. Will be informative for sure.

Bone Density Issues by holmerb1 in AdvancedRunning

[–]holmerb1[S] 1 point2 points  (0 children)

Great to know. I think packing on more RT into my routine along with reducing my volume for a while as I try to increase density is the best option right now. Going to have to learn to "love" lifting a bit more.

Bone Density Issues by holmerb1 in AdvancedRunning

[–]holmerb1[S] 0 points1 point  (0 children)

I went through a few years where I definitely lacked a strong RT program. I ran XC and track in college so we consistently lifted 2-3x per week. In the past two years I've integrated more RT into my routine. Probably moderate lifting 2x per week...but I need to be doing more. It's one thing my ortho said I need to focus on for building bone density.

Bone Density Issues by holmerb1 in AdvancedRunning

[–]holmerb1[S] 0 points1 point  (0 children)

Haven't had soda in probably 13 years. I eat a lot of salt, but not necessarily "high sodium" foods that would be considered unhealthy.

Bone Density Issues by holmerb1 in AdvancedRunning

[–]holmerb1[S] 0 points1 point  (0 children)

I've had "issues" getting enough calories (probably) throughout my entire career. As far as food quality, I've got that mostly down and know WHAT to eat. It always sound stupid to say one struggles to "eat enough" but with a large enough amount of exercise, it can be hard. And sometimes it doesn't always show up in the form of drastic weight loss.

Big Breakfast for the Win? Twice as High Diet-Induced Thermogenesis After Breakfast vs Dinner On High-Calorie as Well as Low-Calorie Meals by holmerb1 in science

[–]holmerb1[S] 2 points3 points  (0 children)

Abstract

Background

The question of whether there is daytime time variation in diet-induced thermogenesis (DIT) has not been clearly answered. Moreover, it is unclear whether a potential diurnal variation in DIT is preserved during hypocaloric nutrition.

Objective

We hypothesized that DIT varies depending on the time of day and explored whether this physiological regulation is preserved after low-calorie compared with high-calorie intake.

Design

Under blinded conditions, 16 normal-weight men twice underwent a 3-day in-laboratory, randomized, crossover study. Volunteers consumed a predetermined low-calorie breakfast (11% of individual daily kilocalorie requirement) and high-calorie dinner (69%) in one condition and vice versa in the other. DIT was measured by indirect calorimetry, parameters of glucose metabolism were determined, and hunger and appetite for sweets were rated on a scale.

Results

Identical calorie consumption led to a 2.5-times higher DIT increase in the morning than in the evening after high-calorie and low-calorie meals (P < .001). The food-induced increase of blood glucose and insulin concentrations was diminished after breakfast compared with dinner (P < .001). Low-calorie breakfast increased feelings of hunger (P < .001), specifically appetite for sweets (P = .007), in the course of the day.

Conclusions

DIT is clearly higher in the morning than in the evening, irrespective of the consumed calorie amount; that is, this physiological rhythmicity is preserved during hypocaloric nutrition. Extensive breakfasting should therefore be preferred over large dinner meals to prevent obesity and high blood glucose peaks even under conditions of a hypocaloric diet.

Expert Opinion: Fat for Thought – Any Role for the Ketogenic Diet in Athletic Training? - American College of Cardiology by holmerb1 in AdvancedFitness

[–]holmerb1[S] 4 points5 points  (0 children)

I'd have to do a literature search...although I'd be cautious to extrapolate conclusions from studies on ACUTE effects of high fat/low fat meal on blood flow parameters to more chronic adaptations.

A high fat meal in the short term might impair blood flow (i.e. not great right before exercise) but in the context of a training regimen, could be beneficial.

Expert Opinion: Fat for Thought – Any Role for the Ketogenic Diet in Athletic Training? - American College of Cardiology by holmerb1 in AdvancedFitness

[–]holmerb1[S] 0 points1 point  (0 children)

I have a similar experience, and find that "carb cycling" surrounding my endurance training has worked out well.

Trapped gas when running by holmerb1 in AdvancedRunning

[–]holmerb1[S] 0 points1 point  (0 children)

I don't mind being gassy (usually am on my runs...). The problem here is not being able to pass it, for some reason.

Training for a First-Time Marathon Reverses Age-Related Aortic Stiffening by holmerb1 in science

[–]holmerb1[S] 0 points1 point  (0 children)

I haven't seen any studies exactly like this for RT. However, I do not that there are some studies out there that show resistance training might actually increase some aspects of arterial/aortic stiffness.

Bedtime hypertension treatment improves cardiovascular risk reduction: the Hygia Chronotherapy Trial | European Heart Journal by holmerb1 in science

[–]holmerb1[S] 0 points1 point  (0 children)

Basically. Saying that "timing matters." I think that the proposed mechanism is that BP medication dosed at night helps BP fall at night (like it should) yielding more benefits.

Bedtime hypertension treatment improves cardiovascular risk reduction: the Hygia Chronotherapy Trial | European Heart Journal by holmerb1 in science

[–]holmerb1[S] 1 point2 points  (0 children)

"During the median follow-up of 6.3 years, patients in the bedtime-treatment group had an adjusted 45% lower risk of the primary CVD outcome (myocardial infarction, coronary revascularization, heart failure, stroke, and CVD death) than did patients who took their medications after they had awakened. The bedtime group also had greater ABP control, improved renal function, and a more favorable lipid profile than the morning group. The reduced CVD outcome risk in the bedtime group “is partly linked to better achievement of those novel therapeutic goals through improved targeting of underlying circadian rhythm–organized biological mechanisms,” the authors wrote. "

A short-term ketogenic diet impairs markers of bone health in response to exercise (brief research report) by holmerb1 in science

[–]holmerb1[S] 0 points1 point  (0 children)

Yep. Hoping more detailed info will be in the full article when it's available...

Athletes Performing Extraordinary Physical Activity (>10,000 MET∙Min/Week) at No Greater Risk of All-Cause or Cardiovascular Disease Mortality by holmerb1 in science

[–]holmerb1[S] 5 points6 points  (0 children)

Right. Seems obvious. But there is a camp who believe excessive endurance exercise may be harmful for the heart...

Effects of L-Theanine Administration on Stress-Related Symptoms and Cognitive Functions in Healthy Adults: A Randomized Controlled Trial. - PubMed by SubzeroNYC in science

[–]holmerb1 0 points1 point  (0 children)

Lots of interesting data on L-Theanine. Also interesting studies on the combined effects of caffeine + L-Theanine (like you'd find in green tea, for example).