Category Archives: Exercise

Paleo Diet Effect on Athletes

hunter, hunting, prehistoric, paleo diet, caveman, saber-toothed tiger, cavewoman

Judging from the article abstract below, it looks like the researchers didn’t find any major impact of the paleo diet on athletic performance, compared to “healthy” control diets. The title of the scientific report is “Paleolithic Diet-Effect on the Health Status and Performance of Athletes?” That sure made me think they were going to look at athletic performance. Here’s one of two sentences in the abstract that refer to athletic performance: “Lower positive impact of paleo diet on performance was observed it the group without exercise.” What does that even mean? Looks like even scientific journals are using click-bait now.

Before you read the abstract, remember that higher blood triglycerides, total cholesterol, and LDL cholesterol are linked in some studies to cardiovascular disease. Also, lower plasma glucose (sugar) and insulin levels are linked in some studies to less risk of cardiovascular disease. So the paleo diet may be healthful since it shifts those numbers in the right direction.

The aim of this meta-analysis was to review the impact of a Paleolithic diet (PD) on selected health indicators (body composition, lipid profile, blood pressure, and carbohydrate metabolism) in the short and long term of nutrition intervention in healthy and unhealthy adults. A systematic review of randomized controlled trials of 21 full-text original human studies was conducted. Both the PD and a variety of healthy diets (control diets (CDs)) caused reduction in anthropometric parameters, both in the short and long term. For many indicators, such as weight (body mass (BM)), body mass index (BMI), and waist circumference (WC), impact was stronger and especially found in the short term. All diets caused a decrease in total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG), albeit the impact of PD was stronger. Among long-term studies, only PD cased a decline in TC and LDL-C. Impact on blood pressure was observed mainly in the short term. PD caused a decrease in fasting plasma (fP) glucose, fP insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) and glycated hemoglobin (HbA1c) in the short run, contrary to CD. In the long term, only PD caused a decrease in fP glucose and fP insulin. Lower positive impact of PD on performance was observed in the group without exercise. Positive effects of the PD on health and the lack of experiments among professional athletes require longer-term interventions to determine the effect of the Paleo diet on athletic performance.

Reference: https://pubmed.ncbi.nlm.nih.gov/33801152/

Click for the full text article. The article title and abstract were so poorly written that I’m not wasting time on the full text. Let me know if you find anything interesting. Furthermore, this “research” was a meta-analysis, so I’m even more skeptical about any conclusions on athletic performance.

Steve Parker, M.D.

How to Prevent Age-Related Muscle Loss

paleo diet, low-carb, Steve Parker MD
This hunter-gatherer snagged himself a brown trout

Axel Sigurdsson, MD, PhD, published a great article on prevention of age-related sarcopenia (loss of muscle mass). Click through for details. To stay vigorous as you age, you should preserve muscle mass and the strength it provides. If you’ve lost muscle mass, you can re-build it. Summary from the good doctor:

Age-related loss of muscle mass (sarcopenia)may start as early as in our thirties and appears to continue for the rest of our lives.

There is also a loss of muscle strength and muscle function. The consequences may often be severe, particularly in the elderly.

Increased physical activity and adequate nutrition are the most powerful tools at our disposal to delay age-related loss of muscle mass.

Well-rounded exercise programs consisting of aerobic and resistance exercises are believed to be most effective

Modification of dietary habits may be an important tool to prevent the decline in muscle mass and function that occurs with aging.

Adequate protein intake is of key importance. Animal-derived protein may provide a higher and broader biological value than vegetable protein.

Fish consumption is recommended and fruits and vegetables should be consumed regularly.

Nutritional supplements containing essential amino acids may be helpful. This is particularly true for whey protein.

Fish-derived protein hydrolysates also appear promising.

Adequate intake of vitamin D is essential.

“Fish-derived protein hydrolysates” doesn’t sound very appetizing. I’ll stick with real fish for now, especially cold-water fatty fish.

Steve Parker, M.D.

What’s the Best Fitness Tracker?

I don’t know. It partially depends on your needs.

ConsumersAdvocate.org has an article comparing and contrasting some of the available fitness trackers:

young woman, exercise, weight training, gym
You go, girl!
HOW WE FOUND THE BEST FITNESS TRACKERFEATURES

We checked for fitness trackers with diverse features that users could choose to best match their lifestyle and goals. This includes multiple health and activity monitoring options.

CONNECTIVITY

Many fitness trackers sync with smartphones or Bluetooth to receive calls, get message notifications, and send data to their corresponding fitness apps. We looked at trackers that were easy to connect.

COST

Regular fitness trackers can range from $50 to $200, while hybrid smartwatches can cost over $400. We compared prices to special features to make sure consumers get the most out of their investment.

CUSTOMER EXPERIENCE

Fitness trackers should be durable, lightweight, and comfortable. We interviewed customers and read dozens of reviews and testimonies for thorough feedback on each product.

Source: The Best Fitness Trackers For 2020

Click through for details. I use none of these trackers, so have no dog in this fight.

Steve Parker, M.D.

Reduce Insulin Resistance with Resistance Training

Didn’t we already know this? The study at hand involved 10 overweight young men.

Insulin is a blood-borne hormone that the pancreas gland secretes in order to keep blood sugar levels from getting too high. (Insulin does many other things, but table that for now.) Insulin triggers certain body cells to absorb glucose from the bloodstream. “Insulin resistance” means that these cells don’t respond to insulin as well as they should, so either the pancreas secretes even more insulin (hyperinsulinemia) or blood sugar levels rise. Insulin resistance is a harbinger of type 2 diabetes mellitus. Most overweight or obese type 2 diabetics have insulin resistance. Many experts think hyperinsulinemia causes disease by itself, regardless of blood sugar levels. So it may be best to avoid insulin resistance and hyperinsulinemia.

The aim of the study was to investigate the effects of 6 weeks of resistance exercise training, composed of one set of each exercise to voluntary failure, on insulin sensitivity and the time course of adaptations in muscle strength/mass. Ten overweight men (age 36 ± 8 years; height 175 ± 9 cm; weight 89 ± 14 kg; body mass index 29 ± 3 kg m−2) were recruited to the study. Resistance exercise training involved three sessions per week for 6 weeks. Each session involved one set of nine exercises, performed at 80% of one‐repetition maximum to volitional failure. Sessions lasted 15–20 min. Oral glucose tolerance tests were performed at baseline and post‐intervention. Vastus lateralis muscle thickness, knee‐extensor maximal isometric torque and rate of torque development (measured between 0 and 50, 0 and 100, 0 and 200, and 0 and 300 ms) were measured at baseline, each week of the intervention, and after the intervention. Resistance training resulted in a 16.3 ± 18.7% (P < 0.05) increase in insulin sensitivity (Cederholm index). Muscle thickness, maximal isometric torque and one‐repetition maximum increased with training, and at the end of the intervention were 10.3 ± 2.5, 26.9 ± 8.3, 18.3 ± 4.5% higher (P < 0.05 for both) than baseline, respectively. The rate of torque development at 50 and 100 ms, but not at 200 and 300 ms, increased (P < 0.05) over the intervention period. Six weeks of single‐set resistance exercise to failure results in improvements in insulin sensitivity and increases in muscle size and strength in young overweight men.

Source: The effect of short‐duration resistance training on insulin sensitivity and muscle adaptations in overweight men – Ismail – 2019 – Experimental Physiology – Wiley Online Library

Steve Parker, M.D.

Image

If You’re Too Weak to Re-Rack Your Weights…

Reduce Your Risk of Cancer By Up to 25%

hypoglycemia, woman, rock-climbing

This activity could increase your odds of accidental death by up to 100%

What I dislike about a phrase like “…up to 25%” is that it includes only 1%.

From UPI:

In findings published Thursday in the Journal of Clinical Oncology, researchers at the National Cancer Institute, the American Cancer Society, and the Harvard T.H. Chan School of Public Health report that people who engaged in physical activity as recommended by the National Institutes of Health were able to reduce their risk for seven different types of cancer by as much as 25 percent.

This included common—and deadly—forms of the disease like colon and breast cancers, as well as endometrial cancer, kidney cancer, myeloma, liver cancer, and non-Hodgkin lymphoma.

*  *  *

Updated federal guidelines for physical activity recommend that people should aim for two and a half to five hours per week of moderate-intensity activity or 75 to 150 minutes per week of “vigorous activity.”

Source: Exercise may reduce risk for cancer by as much as 25 percent – UPI.com

Steve Parker, M.D.

Click pic to purchase book at Amazon.com. E-book versions available at Smashwords.com.

High-Intensity Interval Training (HIIT) Improves Memory in Older Adults, May Prevent Dementia

Steve Parker MD

A slow leisurely pace won’t cut it

Dementia is a devastating and expensive development for an individual and his family. Most dementias are progressive and incurable. If it can be prevented, it should be. Exercise is one preventative. But how much and what kind of exercise?

Nine percent of U.S. adults over 65 have dementia. That’s 3.650,000 folks.

From The Globe and Mail:

In 2017, a team led by the lab’s director, Jennifer Heisz, published a five-year study of more than 1,600 adults older than 65 that concluded that genetics and exercise habits contribute roughly equally to the risk of eventually developing dementia. Only one of those two factors is under your control, so researchers around the world have been striving to pin down exactly what sort of workout routine will best nourish your neurons.

Heisz’s latest study, published last month in the journal Applied Physiology, Nutrition, and Metabolism, offers a tentative answer to this much-debated question. Older adults who sweated through 12 weeks of high-intensity interval training improved their performance on a memory test by 30 per cent compared with those who did a more moderate exercise routine.

This was a small study, only about 20 sedentary participants (all over 60 years old) subjected to one of three protocols for twelve weeks, exercising thrice weekly:

  1. Four-minute bouts of vigorous treadmill walking at 90-95% of maximum heart rate, repeated four times, with three minutes easy walking between the high-intensity spells intervals (HIIT)
  2. Walking at 70-75% of max heart rate for 47 minutes (burning the same number of calories as group #1
  3. Thirty minutes of relaxed stretching

Alex Hutchinson’s full article is well worth a couple minutes of your time if you want to avoid dementia.

Source: New study shows the right workout routine can help fight dementia – The Globe and Mail

Steve Parker, M.D.

Click pic to purchase book at Amazon.com. E-book versions available at Smashwords.com.

Fitness Markers Deteriorate After Just Two Weeks of Sedentary Behavior

Starting a hundred-yard dash

From UPI:

A new study proves that the old adage “use it or lose it” is definitely true when it comes to fitness.After just two weeks of sedentary behavior, formerly fit people had:

—A decline in heart and lung health

—Increased waist circumference

—Greater body fat and liver fat

—Higher levels of insulin resistance

Source: Study: Two weeks of no exercise enough to damage fit people’s bodies – UPI.com

It’s a small study, just 28 subjects, so may not be reproducible.

Steve Parker, M.D.

Click pic to purchase book at Amazon.com

Training for Fitness In Midlife and Beyond

You won’t see her at your home gym

From American Partisan:

If you have chronic pain or have been out of the gym a long time, build up volume (number of sets x number of reps x weight) slowly.  Pick weights you can lift without pain and increase weight and volume in pain-free steps.  The great thing about weight training is it allows you to easily control training variables in a safe, measurable, and repeatable manner while building work capacity and strength.  If one exercise hurts, substitute for another.  For example, if it hurts to back squat, substitute for a front squat….Right now, for example, I’ve built up a bit of pain in my biceps so I’ve substitute pull-ups for chin-ups which seem to take the stress off my biceps due to the weird angle between my upper and lower arms.

Cardio is built-up in a similar manner.  If one thing hurts, do something else or do it only within a pain-free time-interval and intensity to prevent pain flare-ups.  Develop a large variety of ways of doing cardio rather than do the same thing every day since training benefits heavily from novelty.  For example, you can use the assault bike one day, the agility ladder the next, barbell complexes a third day, and agility ladders a fourth day.  If you’re very overweight, start with walking.

Source: Fitness through midlife | American Partisan

The article recommends a book by Bill Hartman called All Gain No Pain. The numerous five-star reviews (and very few with lesser stars) at Amazon.com seem a bit fishy to me due to over-the-top praise and few details. Do you have an opinion on the book?

Check out the quality of Amazon.com book reviews at ReviewMeta.com.

Click pic to purchase book at Amazon.com

Burn More Fat With Interval Training Versus Continuous Exercise

From JAMA Network:

Exercisers can burn slightly more body fat with interval training than moderate-intensity continuous training, according to a recent systematic review and meta-analysis in the British Journal of Sports Medicine. Although the differences in fat loss weren’t huge, the interval workouts were shorter, which could make it easier for people to adhere to them.

Source: For Fat Burning, Interval Training Beats Continuous Exercise | Lifestyle Behaviors | JAMA | JAMA Network

Click pic to purchase book at Amazon in the U.S.