MyMedR

Displaying all 9 publications

Abstract:

Sort:

Central effects of mouth rinses on endurance and strength performance

Tan SH, Khong TK, Selvanayagam VS, Yusof A

Eur J Appl Physiol, 2024 Feb;124(2):403-415.
PMID: 38038740 DOI: 10.1007/s00421-023-05350-w

Rinsing the mouth with a carbohydrate (CHO) solution has been shown to enhance exercise performance while reducing neuromuscular fatigue. This effect is thought to be mediated through the stimulation of oral receptors, which activate brain areas associated with reward, motivation, and motor control. Consequently, corticomotor responsiveness is increased, leading to sustained levels of neuromuscular activity prior to fatigue. In the context of endurance performance, the evidence regarding the central involvement of mouth rinse (MR) in performance improvement is not conclusive. Peripheral mechanisms should not be disregarded, particularly considering factors such as low exercise volume, the participant's fasting state, and the frequency of rinsing. These factors may influence central activations. On the other hand, for strength-related activities, changes in motor evoked potential (MEP) and electromyography (EMG) have been observed, indicating increased corticospinal responsiveness and neuromuscular drive during isometric and isokinetic contractions in both fresh and fatigued muscles. However, it is important to note that in many studies, MEP data were not normalised, making it difficult to exclude peripheral contributions. Voluntary activation (VA), another central measure, often exhibits a lack of changes, mainly due to its high variability, particularly in fatigued muscles. Based on the evidence, MR can attenuate neuromuscular fatigue and improve endurance and strength performance via similar underlying mechanisms. However, the evidence supporting central contribution is weak due to the lack of neurophysiological measures, inaccurate data treatment (normalisation), limited generalisation between exercise modes, methodological biases (ignoring peripheral contribution), and high measurement variability.Trial registration: PROSPERO ID: CRD42021261714.

Matched MeSH terms: Carbohydrates/pharmacology
Carbohydrate mouth rinse is no more effective than placebo on running endurance of dehydrated and heat acclimated athletes

Kamaruddin HK, Farah NMF, Aziz AR, Mündel T, Che Muhamed AM

Eur J Appl Physiol, 2023 Jul;123(7):1507-1518.
PMID: 36920510 DOI: 10.1007/s00421-023-05170-y

PURPOSE: To determine whether carbohydrate mouth rinsing would improve endurance running performance of tropical natives in a warm-humid (30 °C and 70% relative humidity) environment.
METHOD: Twelve endurance male runners [age 25 ± 3 years; peak aerobic capacity ([Formula: see text]O2peak) 57.6 ± 3.6 mL.kg-1.min-1] completed three time-to-exhaustion (TTE) trials at ~ 70% [Formula: see text]O2peak while swilling 25 ml of a 6% carbohydrate (CHO) or taste-matched placebo (PLA) as well as no mouth rinse performed in the control (CON) trial.
RESULTS: TTE performance was significantly longer in both CHO and PLA trials when compared with the CON trial (54.7 ± 5.4 and 53.6 ± 5.1 vs. 48.4 ± 3.6 min, respectively; p 0.05). Similarly, plasma lactate and glucose as well as exercise heart rate were not influenced by the trials.
CONCLUSIONS: The present study demonstrates that mouth rinsing, whether carbohydrate or placebo, provides an ergogenic benefit to running endurance when compared to CON in a heat stress environment. Nevertheless, the results do not support the notion that rinsing a carbohydrate solution provides a greater advantage as previously described among non-heat acclimated individuals within a temperate condition.

Matched MeSH terms: Dietary Carbohydrates/pharmacology
Cryopreservation of scalps of Malaysian bananas using a pre-growth method

Sipen P, Anthony P, Davey MR

Cryo Letters, 2011 May-Jun;32(3):197-205.
PMID: 21766149

The effect of preculture with different sugars and mannitol on cryopreservation of scalps of the banana (Musa) cvs. Pisang Mas, Pisang Nangka, Pisang Berangan and Pisang Awak was investigated. Scalps (0.3 square cm) were precultured on semi-solid MS-based medium, containing 0.4 or 0.5 M sucrose, glucose, fructose, trehalose or mannitol, for 14 days under a 16 h light and 8 h dark photoperiod prior to rapid cooling and storage in liquid nitrogen. Explants were rewarmed rapidly in a water bath at 40 degree C for 1 min, followed by recovery on two layers of sterile filter paper overlaying 25 ml aliquots of semi-solid MS-based medium with 5 mg per liter benzylaminopurine, 0.2 mg per liter indole acetic acid and 10 mg per liter ascorbic acid (PM8 medium) for 2 days in the dark. Subsequently, scalps were transferred onto 25 ml aliquots of semi-solid PM8 medium and incubated in the dark for 1 week prior to incubation in the light. Shoot regeneration from 5 - 48 percent of cryopreserved scalps of all the banana cvs., was observed only following preculture with 0.4 or 0.5 M glucose or fructose, and with 0.4 M trehalose for the cvs. Pisang Berangan and Pisang Awak. Preculture with 0.4 M glucose resulted in maximum shoot regeneration of cryopreserved scalps of 10 percent, 13 percent, 42 percent and 48 percent for the cvs. Pisang Mas, Pisang Nangka, Pisang Berangan and Pisang Awak, respectively. Concentrations of 0.5 M trehalose, or 0.4 and 0.5 M sucrose or mannitol were extremely toxic to scalps of all the cvs. investigated.

Matched MeSH terms: Carbohydrates/pharmacology*
Combination of sago and soy-protein supplementation during endurance cycling exercise and subsequent high-intensity endurance capacity

Ghosh AK, Rahaman AA, Singh R

Int J Sport Nutr Exerc Metab, 2010 Jun;20(3):216-23.
PMID: 20601739

The purpose of the study was to investigate whether a combination of sago and soy protein ingested during moderate-intensity cycling exercise can improve subsequent high-intensity endurance capacity compared with a carbohydrate in the form of sago and with a placebo. The participants were 8 male recreational cyclists with age, weight, and VO2max of 21.5 +/- 1.1 yr, 63.3 +/- 2.4 kg, and 39.9 +/- 1.1 ml . kg(-1) . min(-1), respectively. The design of the study was a randomized, double-blind placebo-controlled crossover comprising 60 min of exercise on a cycle ergometer at 60% VO2max followed by a time-to-exhaustion ride at 90% VO2max. The sago feeding provided 60 g of carbohydrate, and the sago-soy combination provided 52.5 g of carbohydrate and 15 g of protein, both at 20-min intervals during exercise. Times to exhaustion for the placebo, sago, and sago-soy supplementations were 4.09 +/- 1.28, 5.49 +/- 1.20, and 7.53 +/- 2.02 min, respectively. Sago-soy supplementation increased endurance by 84% (44-140%; p < .001) and by 37% (15-63%; p < .05) relative to placebo and sago, respectively. The plasma insulin response was elevated above that with placebo during sago and sago-soy supplementations. The authors conclude that a combination of sago and soy protein can delay fatigue during high-intensity cycling.

Matched MeSH terms: Dietary Carbohydrates/pharmacology*
Effects of varying dietary carbohydrate levels on growth performance, body composition and liver histology of Malaysian mahseer fingerlings (Tor tambroides)

Ishak SD, Kamarudin MS, Ramezani-Fard E, Saad CR, Yusof YA

J Environ Biol, 2016 07;37(4 Spec No):755-64.
PMID: 28779735

We investigated the effects of four iso-nitrogenous (40% crude protein) and iso-caloric (17.6 kJ g(-1)) diets with different dietary carbohydrate levels (15%, 20%, 25% and 30%) on the growth performance, feed utilization efficiency, body composition and liver histology of Malaysian mahseer (Tor tambroides) fingerlings in a 10-week feeding trial. Fish (initial weight of 0.8?0.1 g; initial total length 4.2?0.1 cm) were fed twice daily at 4% body mass. Dietary carbohydrate level had significant effects (P<0.05) on weight gain, SGR (specific growth rate), FCR (feed conversion rate), PER (protein efficiency rate), survival percentage and all nutrient retention values (PRV, LRV, CRV, ERV). Protein, carbohydrate and gross energy composition of the fish body were also significantly differed (P<0.05) among treatments. Liver histology showed mild hepatic steatosis and hypertrophy for fishes receiving a higher dietary carbohydrate inclusion. In general, treatments with 20% and 25% dietary carbohydrate levels produced better growth results compared to the rest of the treatments. Using a second-order polynomial regression analysis model, the optimal dietary carbohydrate level of 23.4% was estimated for mahseer fingerlings. ?

Matched MeSH terms: Dietary Carbohydrates/pharmacology*
Effect of sugars on characteristics of Boer goat semen after cryopreservation

Naing SW, Wahid H, Mohd Azam K, Rosnina Y, Zuki AB, Kazhal S, et al.

Anim. Reprod. Sci., 2010 Oct;122(1-2):23-8.
PMID: 20637550 DOI: 10.1016/j.anireprosci.2010.06.006

In order to improve Boer goat semen quality during cryopreservation process, the influence of sugar supplementation on semen characteristics of sperm were investigated. Three experiments were carried out to investigate the effect of (a) addition of two monosaccharides (fructose and glucose) and two disaccharides sugars (trehalose and sucrose) (b) sugar combination (fructose and trehalose, sucrose and trehalose, glucose and trehalose), and control (glucose without trehalose) (c) different concentrations of trehalose on cryopreservation using Tris based extender. The total motility, forward motility, viability, normal spermatozoa, acrosome integrity and membrane integrity were assessed subjectively. Differences were not detected among monosaccharides, but glucose increased (P<0.05) sperm forward motility in post-thaw goat semen compared to trehalose or sucrose supplementation. Semen quality did not differ (P>0.05) among disaccharide sugar supplementation. Combination of glucose and trehalose significantly improved the characteristics of Boer spermatozoa after cryopreservation (P<0.05). Supplementation of trehalose (198.24mM) into the glucose extender significantly increased total motility, forward motility, live spermatozoa, acrosome integrity and membrane integrity following cryopreservation (P<0.05). In conclusion, glucose had the better ability to support Boer sperm motility and movement patterns. Combination of monosaccharide (glucose) and disaccharide (trehalose) improved semen quality following cryopreservation. Trehalose supplementation at the concentration of 198.24mM to the glucose extender conferred the greater improvement of semen quality for Boer semen cryopreservation.

Matched MeSH terms: Carbohydrates/pharmacology*
Fulltext Impact of liver fat on the differential partitioning of hepatic triacylglycerol into VLDL subclasses on high and low sugar diets

Umpleby AM, Shojaee-Moradie F, Fielding B, Li X, Marino A, Alsini N, et al.

Clin Sci (Lond), 2017 Nov 01;131(21):2561-2573.
PMID: 28923880 DOI: 10.1042/CS20171208

Dietary sugars are linked to the development of non-alcoholic fatty liver disease (NAFLD) and dyslipidaemia, but it is unknown if NAFLD itself influences the effects of sugars on plasma lipoproteins. To study this further, men with NAFLD (n = 11) and low liver fat 'controls' (n = 14) were fed two iso-energetic diets, high or low in sugars (26% or 6% total energy) for 12 weeks, in a randomised, cross-over design. Fasting plasma lipid and lipoprotein kinetics were measured after each diet by stable isotope trace-labelling.There were significant differences in the production and catabolic rates of VLDL subclasses between men with NAFLD and controls, in response to the high and low sugar diets. Men with NAFLD had higher plasma concentrations of VLDL1-triacylglycerol (TAG) after the high (P<0.02) and low sugar (P<0.0002) diets, a lower VLDL1-TAG fractional catabolic rate after the high sugar diet (P<0.01), and a higher VLDL1-TAG production rate after the low sugar diet (P<0.01), relative to controls. An effect of the high sugar diet, was to channel hepatic TAG into a higher production of VLDL1-TAG (P<0.02) in the controls, but in contrast, a higher production of VLDL2-TAG (P<0.05) in NAFLD. These dietary effects on VLDL subclass kinetics could be explained, in part, by differences in the contribution of fatty acids from intra-hepatic stores, and de novo lipogenesis. The present study provides new evidence that liver fat accumulation leads to a differential partitioning of hepatic TAG into large and small VLDL subclasses, in response to high and low intakes of sugars.

Matched MeSH terms: Dietary Carbohydrates/pharmacology
Potential Functional Byproducts from Guava Purée Processing

Lim SY, Tham PY, Lim HYL, Heng WS, Chang YP

J Food Sci, 2018 Jun;83(6):1522-1532.
PMID: 29745989 DOI: 10.1111/1750-3841.14155

The valorization of guava waste requires compositional and functional studies. We tested three byproducts of guava purée processing, namely refiner, siever, and decanter. We analyzed the chemical composition and quantified the prebiotic activity score and selected carbohydrates; we also determined the water holding (WHC), oil holding (OHC), cation exchange capacities, bile acid binding, and glucose dialysis retardation (GDR) of the solid fraction and the antioxidative and α-amylase inhibitory capacities (AIC) of the ethanolic extract. Refiner contained 7.7% lipid, 7.08% protein and a relatively high phytate content; it had a high prebiotic activity score and possessed the highest binding capacity with deoxycholic acid. Siever contained high levels of low molecular weight carbohydrates and total tannin but relatively low crude fiber and cellulose contents. It had the highest binding with chenodeoxycholic acid (74.8%), and exhibited the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity. Decanter was rich in cellulose and had a high prebiotic activity score. The WHC and OHC values of decanter were within a narrow range and also exhibited the highest binding with cholic acid (86.6%), and the highest values of GDR and AIC. The refiner waste could be included in animal feed but requires further processing to reduce the high phytate levels. All three guava byproducts had the potential to be a source of antioxidant dietary fiber (DF), a finding that warrants further in vivo study.
PRACTICAL APPLICATION: To differing extents, the guava byproducts exhibited useful physicochemical binding properties and so possessed the potential for health-promoting activity. These byproducts could also be upgraded to other marketable products so the manufacturers of processed guava might be able to develop their businesses sustainably by making better use of them.

Matched MeSH terms: Carbohydrates/pharmacology
Glycemic responses of patients with type 2 diabetes to individual carbohydrate-rich foods and mixed meals

Robert SD, Ismail AA

Ann Nutr Metab, 2012;60(1):27-32.
PMID: 22212476 DOI: 10.1159/000335224

Our purpose was to determine whether the glycemic index (GI) of individual foods applies to mixed meals.

Matched MeSH terms: Dietary Carbohydrates/pharmacology*