Thursday, May 16, 2024

Different Supplementation For Resistance Exercise

From several years ago, here is a paper on a specific supplementation intake regimen for resistance training. Abstract:


Lowery, RP, Joy, JM, Rathmacher, JA, Baier, SM, Fuller, JC Jr, Shelley, MC II, Jäger, R, Purpura, M, Wilson, SMC, and Wilson, JM. Interaction of beta-hydroxy-beta-methylbutyrate free acid and adenosine triphosphate on muscle mass, strength, and power in resistance trained individuals. J Strength Cond Res 30(7): 1843-1854, 2016-Adenosine-5'-triphosphate (ATP) supplementation helps maintain performance under high fatiguing contractions and with greater fatigue recovery demands also increase. Current evidence suggests that the free acid form of β-hydroxy-β-methylbutyrate (HMB-FA) acts by speeding regenerative capacity of skeletal muscle after high-intensity or prolonged exercise. Therefore, we investigated the effects of 12 weeks of HMB-FA (3 g) and ATP (400 mg) administration on lean body mass (LBM), strength, and power in trained individuals. A 3-phase double-blind, placebo-, and diet-controlled study was conducted. Phases consisted of an 8-week periodized resistance training program (phase 1), followed by a 2-week overreaching cycle (phase 2), and a 2-week taper (phase 3). Lean body mass was increased by a combination of HMB-FA/ATP by 12.7% (p < 0.001). In a similar fashion, strength gains after training were increased in HMB-FA/ATP-supplemented subjects by 23.5% (p < 0.001). Vertical jump and Wingate power were increased in the HMB-FA/ATP-supplemented group compared with the placebo-supplemented group, and the 12-week increases were 21.5 and 23.7%, respectively. During the overreaching cycle, strength and power declined in the placebo group (4.3-5.7%), whereas supplementation with HMB-FA/ATP resulted in continued strength gains (1.3%). In conclusion, HMB-FA and ATP in combination with resistance exercise training enhanced LBM, power, and strength. In addition, HMB-FA plus ATP blunted the typical response to overreaching, resulting in a further increase in strength during that period. It seems that the combination of HMB-FA/ATP could benefit those who continuously train at high levels such as elite athletes or military personnel.

This may be of interest to high-intensity trainees.

Thursday, April 11, 2024

Meal Delivery And Elder Feeding

Home-delivered meal programs help elder diets, abstract:

BACKGROUND:
Poor diet quality and insufficient nutrient intake is of particular concern among older adults. The Older Americans Act of 1965 authorizes home-delivered meal services to homebound individuals aged 60 years and older.
OBJECTIVE:
The purpose of this study was to review scientific evidence on the impact of home-delivered meal services on diet and nutrition among recipients.
METHODS:
Keyword and reference searches were conducted in Cochrane Library, Google Scholar, PubMed and Web of Science. Inclusion criteria included: study design (randomized controlled trials, cohort studies, pre-post studies, or cross-sectional studies); main outcome (food and nutrient intakes); population (home-delivered meal program participants); country (US); language (articles written in English); and article type (peer-reviewed publications or theses).
RESULTS:
Eight studies met the inclusion criteria, including two randomized controlled trial studies (from the same intervention), one cohort study, two pre-post studies, and three cross-sectional studies. All but two studies found home-delivered meal programs to significantly improve diet quality, increase nutrient intakes, and reduce food insecurity and nutritional risk among participants. Other beneficial outcomes include increased socialization opportunities, improvement in dietary adherence, and higher quality of life.
CONCLUSIONS:
Home-delivered meal programs improve diet quality and increase nutrient intakes among participants. These programs are also aligned with the federal cost-containment policy to rebalance long-term care away from nursing homes to home- and community-based services by helping older adults maintain independence and remain in their homes and communities as their health and functioning decline.

As families are scattered about, particularly in the USA, it is important that some infrastructure exists to ensure older people have adequate dietary intake.

Thursday, March 21, 2024

Resistance Training Restores Muscle Sensitivity To Feeding

An interesting paper on exercise, feeding, and muscle; abstract:

Normally, skeletal muscle mass is unchanged, beyond periods of growth, but it begins to decline in the fourth or fifth decade of life. The mass of skeletal muscle is maintained by ingestion of protein-containing meals. With feeding, muscle protein synthesis (MPS) is stimulated and a small suppression of muscle protein breakdown (MPB) occurs, such that protein balance becomes positive (MPS>MPB). As the postprandial period subsides and a transition toward fasting occurs, the balance of muscle protein turnover becomes negative again (MPB>MPS). Thus, during maintenance of skeletal muscle mass, the long-term net result is that MPS is balanced by MPB. Acutely, however, it is of interest to determine what regulates feeding-induced increases in MPS, since it appears that, in a number of scenarios (for example aging, disuse, and wasting diseases), a suppression of MPS in response to feeding is a common finding. In fact, recent findings point to the fact that loss of skeletal muscle mass with disuse and aging is due not chronic changes in MPS or MPB, but to a blunted feeding-induced rise in MPS. Resistance exercise is a potent stimulator of MPS and appears to synergistically enhance the gains stimulated by feeding. As such, resistance exercise is an important countermeasure to disuse atrophy and to age-related declines in skeletal muscle mass. What is less well understood is how the intensity and volume of the resistance exercise stimulus is sufficient to result in rises in MPS. Recent advances in this area are discussed here, with a focus on human in vivo data.

To summarize: feeding, particularly of protein, favors muscle buildup as opposed t breakdown and fasting does the opposite.  Muscle loss with age seems linked to suppressed muscle buildup from feeding and this suppression can be reduced by resistance training.  Therefore, resistance training helps to reduce/prevent age-related muscle loss, possibly through enhancing feeding-related stimulation of muscle protein synthesis.  Hence the importance of resistance training and (protein) feeding (albeit of course not in excess).

Coffee And Cancer Risk

Here is a paper on coffee consumption and cancer risk from several years ago,  Bottom like is that there doesn't seem to be a big effect either way; coffee can cause decreased risk for some cancers, but possibly increased risk for childhood leukemia with maternal coffee drinking during pregnancy. The data are "limited and inconsistent" in some cases; overall it seems like a "wash" based on these findings, no big effect. Abstract:
We reviewed available evidence on coffee drinking and the risk of all cancers and selected cancers updated to May 2016. Coffee consumption is not associated with overall cancer risk. A meta-analysis reported a pooled relative risk (RR) for an increment of 1 cup of coffee/day of 1.00 [95% confidence interval (CI): 0.99-1.01] for all cancers. Coffee drinking is associated with a reduced risk of liver cancer. A meta-analysis of cohort studies found an RR for an increment of consumption of 1 cup/day of 0.85 (95% CI: 0.81-0.90) for liver cancer and a favorable effect on liver enzymes and cirrhosis. Another meta-analysis showed an inverse relation for endometrial cancer risk, with an RR of 0.92 (95% CI: 0.88-0.96) for an increment of 1 cup/day. A possible decreased risk was found in some studies for oral/pharyngeal cancer and for advanced prostate cancer. Although data are mixed, overall, there seems to be some favorable effect of coffee drinking on colorectal cancer in case-control studies, in the absence of a consistent relation in cohort studies. For bladder cancer, the results are not consistent; however, any possible direct association is not dose and duration related, and might depend on a residual confounding effect of smoking. A few studies suggest an increased risk of childhood leukemia after maternal coffee drinking during pregnancy, but data are limited and inconsistent. Although the results of studies are mixed, the overall evidence suggests no association of coffee intake with cancers of the stomach, pancreas, lung, breast, ovary, and prostate overall. Data are limited, with RR close to unity for other neoplasms, including those of the esophagus, small intestine, gallbladder and biliary tract, skin, kidney, brain, thyroid, as well as for soft tissue sarcoma and lymphohematopoietic cancer.

I don't drink coffee myself, but based on these data overall it seems not do any harm taking all risks together - although pregnant women may want to ask their doctor about the risk in that specific case.

Thursday, February 15, 2024

Dietary Lapses

What is the frequency and predictors of dietary lapses?  A paper from several years ago looks into this, abstract:

BACKGROUND:
Adherence to dietary prescriptions is critical for successful weight loss and weight loss maintenance. However, research on specific instances of inadherence (lapses) is limited, and findings regarding the frequency, nature, and causes of lapses are mixed. Additionally, no studies have examined lapses over the course of a weight loss program.
PURPOSE:
In the context of a reduced calorie diet prescribed as part of a behavioral treatment, we aimed to characterize lapse occurrence, examine lapse frequency across treatment, examine predictors of lapses, and assess the relationship between lapses and weight loss.
METHODS:
Adults (n = 189) enrolled in a 12-month behavioral weight loss program completed ecological momentary assessment (EMA) at baseline, mid-treatment, and end of treatment. At each EMA survey, participants indicated whether a lapse had occurred, and responded to questions assessing situational, environmental, and affective states.
RESULTS:
Lapse frequency showed a curvilinear relationship over time, such that frequency first decreased and then increased. Lapse frequency at baseline was negatively associated with early and overall weight loss. Lapses most often occurred at home, in the evenings, on the weekends, and entailed eating a forbidden food. Greater overall levels of assessed affective and environmental triggers predicted lapses, and greater momentary hunger and deprivation, and the presence of palatable food, also prospectively predicted lapses.
CONCLUSIONS:
In addition to characterizing lapse frequency, the current study identified prospective predictors of lapses across treatment. These findings support the importance of lapses to weight control and provide insight for potential targets of intervention to prevent lapse occurrence.

One point I would raise in response to: "Lapses most often occurred at home, in the evenings, on the weekends, and entailed eating a forbidden food. Greater overall levels of assessed affective and environmental triggers predicted lapses, and greater momentary hunger and deprivation, and the presence of palatable food, also prospectively predicted lapses" is to suggest that a pre-planned cheat meal (for those more overweight) or cheat day (or those who cab be more flexible, who have less weight to lose) may alleviate some of these problems.  The key is discipline, not to "cheat" all week.  "Cheating" may help reset metabolism and leptin levels and avoid the slowing of metabolism that accompanies dieting (although this requires more evidence).  The psychological benefits are obvious.

Thursday, January 18, 2024

Resistance Training And Muscle Metabolism

Here is a paper from several years ago formally demonstrating what bodybuilders have long put into practice: resistance training affects protein turnover in skeletal muscle so as to result in muscle growth.  Abstract:

PURPOSE:
Acute bouts of resistance exercise and subsequent training alters protein turnover in skeletal muscle. The mechanisms responsible for the changes in basal post-absorptive protein turnover and its impact on muscle hypertrophy following resistance exercise training are unknown. Our goal was to determine whether post-absorptive muscle protein turnover following 12 weeks of resistance exercise training (RET) plays a role in muscle hypertrophy. In addition, we were interested in determining potential molecular mechanisms responsible for altering post-training muscle protein turnover.
METHODS:
Healthy young men (n = 31) participated in supervised whole body progressive RET at 60-80% 1 repetition maximum (1-RM), 3 days/week for 3 months. Pre- and post-training vastus lateralis muscle biopsies and blood samples taken during an infusion of 13C6 and 15N phenylalanine and were used to assess skeletal muscle protein turnover in the post-absorptive state. Lean body mass (LBM), muscle strength (determined by dynamometry), vastus lateralis muscle thickness (MT), myofiber type-specific cross-sectional area (CSA), and mRNA were assessed pre- and post-RET.
RESULTS:
RET increased strength (12-40%), LBM (~5%), MT (~15%) and myofiber CSA (~20%) (p < 0.05). Muscle protein synthesis (MPS) increased 24% while muscle protein breakdown (MPB) decreased 21%, respectively. These changes in protein turnover resulted in an improved net muscle protein balance in the basal state following RET. Further, the change in basal MPS is positively associated (r = 0.555, p = 0.003) with the change in muscle thickness.
CONCLUSION:
Post-absorptive muscle protein turnover is associated with muscle hypertrophy during resistance exercise training.

It is always comforting when science supports popular conception.

Thursday, December 21, 2023

Diet And Cardiometabolic Deaths

From several years ago is a study the emphasizes what we should all hopefully already know - some foods increase the risk of death from cardiovascular events and other foods decrease that risk.  Here is the Results section from the Abstract; I am bold-fonting the important points for ease of reading:

RESULTS:In 2012, 702 308 cardiometabolic deaths occurred in US adults, including 506 100 from heart disease (371 266 coronary heart disease, 35 019 hypertensive heart disease, and 99 815 other cardiovascular disease), 128 294 from stroke (16 125 ischemic, 32 591 hemorrhagic, and 79 578 other), and 67 914 from type 2 diabetes. Of these, an estimated 318 656 (95% uncertainty interval [UI], 306 064-329 755; 45.4%) cardiometabolic deaths per year were associated with suboptimal intakes-48.6% (95% UI, 46.2%-50.9%) of cardiometabolic deaths in men and 41.8% (95% UI, 39.3%-44.2%) in women; 64.2% (95% UI, 60.6%-67.9%) at younger ages (25-34 years) and 35.7% (95% UI, 33.1%-38.1%) at older ages (≥75 years); 53.1% (95% UI, 51.6%-54.8%) among blacks, 50.0% (95% UI, 48.2%-51.8%) among Hispanics, and 42.8% (95% UI, 40.9%-44.5%) among whites; and 46.8% (95% UI, 44.9%-48.7%) among lower-, 45.7% (95% UI, 44.2%-47.4%) among medium-, and 39.1% (95% UI, 37.2%-41.2%) among higher-educated individuals. The largest numbers of estimated diet-related cardiometabolic deaths were related to high sodium (66 508 deaths in 2012; 9.5% of all cardiometabolic deaths), low nuts/seeds (59 374; 8.5%), high processed meats (57 766; 8.2%), low seafood omega-3 fats (54 626; 7.8%), low vegetables (53 410; 7.6%), low fruits (52 547; 7.5%), and high SSBs (51 694; 7.4%). Between 2002 and 2012, population-adjusted US cardiometabolic deaths per year decreased by 26.5%. The greatest decline was associated with insufficient polyunsaturated fats (-20.8% relative change [95% UI, -18.5% to -22.8%]), nuts/seeds (-18.0% [95% UI, -14.6% to -21.0%]), and excess SSBs (-14.5% [95% UI, -12.0% to -16.9%]). The greatest increase was associated with unprocessed red meats (+14.4% [95% UI, 9.1%-19.5%]).

Talk to your physician about adjusting your diet accordingly. SSBs = sugar-sweetened beverages.

Thursday, November 23, 2023

A Gentleman's Agreement

Another article about the gut microbiota and immunity is here.  Abstract:

Our body is colonized by more than a hundred trillion commensals, represented by viruses, bacteria and fungi. This complex interaction has shown that the microbiome system contributes to the host's adaptation to its environment, providing genes and functionality that give flexibility of diet and modulate the immune system in order not to reject these symbionts. In the intestine, specifically, the microbiota helps developing organ structures, participates of the metabolism of nutrients and induces immunity. Certain components of the microbiota have been shown to trigger inflammatory responses, whereas others, anti-inflammatory responses. The diversity and the composition of the microbiota, thus, play a key role in the maintenance of intestinal homeostasis and explain partially the link between intestinal microbiota changes and gut-related disorders in humans. Tight junction proteins are key molecules for determination of the paracellular permeability. In the context of intestinal inflammatory diseases, the intestinal barrier is compromised, and decreased expression and differential distribution of tight junction proteins is observed. It is still unclear what is the nature of the luminal or mucosal factors that affect the tight junction proteins function, but the modulation of the immune cells found in the intestinal lamina propria is hypothesized as having a role in this modulation. In this review, we provide an overview of the current understanding of the interaction of the gut microbiota with the immune system in the development and maintenance of the intestinal barrier.

Immunity and maintenance of the intestinal barrier - crucial to health - are strongly affected by the composition of the gut microbiota, which in turn is strongly affected by diet.  High fiber, active culture yogurt - these are part of a healthy diet and can help maintain a better gut profile.

Thursday, October 19, 2023

Maintaining Lean Body Mass While "Cutting"

A regimen for maintaining lean body mass while "cutting" for a drug-free physique competition was studied in a female competitor.  Abstract:


To achieve the criterion appearance prior to competing in a physique competition, athletes undergo preparatory regimens involving high-volume intense resistance and aerobic exercise with hypocaloric energy intake. As the popularity of "drug-free" competition increases, more athletes are facing this challenge without the recuperative advantage provided by performance-enhancing drugs. Consequently, the likelihood of loss of lean body and/or bone mass is increased. The purpose of this investigation was to monitor changes in body composition for a 29-year-old self-proclaimed drug-free female figure competitor during a 32-week preparatory regimen comprising high-volume resistance and aerobic exercise with hypocaloric energy intake. We used dual-energy x-ray absorptiometry (DXA) to evaluate regional fat and bone mineral density. During the initial 22 weeks, the subject reduced energy intake and engaged in resistance (4-5 sessions/week) and aerobic (3 sessions/week) training. During the final 10 weeks, the subject increased exercise frequency to 6 (resistance) and 4 (aerobic) sessions/week while ingesting 1130-1380 kcal/day. During this 10-week period, she consumed a high quantity of protein (~55% of energy intake) and nutritional supplements. During the 32 weeks, body mass and fat mass decreased by 12% and 55%, respectively. Conversely, lean body mass increased by 1.5%, an amount that exceeded the coefficient of variation associated with DXA-derived measurement. Total bone mineral density was unchanged throughout. In summary, in preparation for a figure competition, a self-proclaimed drug-free female achieved the low body-fat percentage required for success in competition without losing lean mass or bone density by following a 32-week preparatory exercise and nutritional regimen.

Thus, consistent with popular conception, a high protein intake was associated with maintenance (actually increase) with decreased body mass and fat mass.  High volume exercise and calorie-cutting were all part of the mix, also consistent with popular practice.


Thursday, September 21, 2023

Gene Therapy For Sickle Cell Disease

Here is a paper from several years ago, abstract:

Sickle cell disease results from a homozygous missense mutation in the β-globin gene that causes polymerization of hemoglobin S. Gene therapy for patients with this disorder is complicated by the complex cellular abnormalities and challenges in achieving effective, persistent inhibition of polymerization of hemoglobin S. We describe our first patient treated with lentiviral vector-mediated addition of an antisickling β-globin gene into autologous hematopoietic stem cells. Adverse events were consistent with busulfan conditioning. Fifteen months after treatment, the level of therapeutic antisickling β-globin remained high (approximately 50% of β-like-globin chains) without recurrence of sickle crises and with correction of the biologic hallmarks of the disease. (Funded by Bluebird Bio and others; HGB-205 ClinicalTrials.gov number, NCT02151526 .).

So, fifteen months of continued therapeutic benefit was observed.  That's very good and stable for that time period. We'll need to look into, and follow up on, continuing developments in this field; but in general, gene therapy opens up exciting avenues of novel therapeutics to treat a variety of inherited and sporadic disorders.