Effects Of Carbohydrate Supplementation Research Articles

Injection of pidgovlі bjolin family with glucose-fructose syrup on the effectiveness of growing bjolin uterus

On the development and productivity of bjolin queens, they infuse the methods of vivennya, dew vivification, weather conditions, and the appearance of food - bee bread and honey, or a square file and nectar. On a practical basis, the preparation of the large family of creepers with food, additional supplies of small private substitutes, one of such substitutes is glucose-fructose syrup. The purpose of this work was to study the effect of carbohydrate supplementation with glucose-fructose syrup in foster families on the number and weight of reared queens in the context of supportive honey. In the statistic, it has been infused into the adolescent bjolin family with glucose-fructose syrup on the efficiency of the growth of bjolin queen bees. The pre-session was carried out at the base of the PP “Volodymyr” with. Shershny Tivrivsky district of the Vinnytsia region. In the past year, in the year of the bdzholin family, glucose-fructose syrup was revealed, which shortens the result of the reception of larvae per vykhovannya to preserve in the previous groups by 12.5 % more portions of the control group in bjolins. The water hour revealed a decrease in vibrating mothers by 10.5 %, depending on the control group, in which case the indicator of the increase in changes was made. In the results of the last few days, it was established that the introduction of glucose-fructose syrup to the last group of glucose-fructose syrup to the last group was increased, and the increase in the intensity of the growth of the bjolin queens became freely average, to a maximum of 20.3 % for the group. Thus, the obtained data indicate the effectiveness of the effect of glucose-fructose syrup during feeding in foster families on the number and weight of reared queens.

Carbohydrates on the growth of Cattleya schilleriana Reichb.f. seedlings (Orchidaceae)

ABSTRACT: The aim of the present study was to evaluate the effects of carbohydrate supplementation on the propagation of the orchid Cattleya schilleriana. The 120-d-old seedlings were subcultured in fructose-, glucose-, or sucrose-supplemented (0, 15, 30, and 45g L-1) ½ MS culture medium (half-strength macronutrient concentrations), using a completely random design with four repetitions per treatment. After 120d of treatment, root number and length, leaf number and length, and fresh weight were evaluated, and seedling survival was evaluated after 75d of acclimatization in a greenhouse. The in vitro growth data were submitted to regression analysis, whereas the percentage survival data were analyzed using ANOVA and Tukey’s test. Both in vitro growth and ex vitro survival were lowest when the plantlets were grown in the absence of a carbohydrate source and highest (>90% survival) when supplemented with glucose. According to our findings, the addition of either glucose (30g L-1) or sucrose (30g L-1) is recommended for mass propagation of C. schilleriana.

Effect of Carbohydrate Supplementation on Investment into Offspring Number, Size, and Condition in a Social Insect.

Resource availability can determine an organism’s investment strategies for growth and reproduction. When nutrients are limited, there are potential tradeoffs between investing into offspring number versus individual offspring size. In social insects, colony investment in offspring size and number may shift in response to colony needs and the availability of food resources. We experimentally manipulated the diet of a polymorphic ant species (Solenopsis invicta) to test how access to the carbohydrate and amino acid components of nectar resources affect colony investment in worker number, body size, size distributions, and individual percent fat mass. We reared field-collected colonies on one of four macronutrient treatment supplements: water, amino acids, carbohydrates, and amino acid and carbohydrates. Having access to carbohydrates nearly doubled colony biomass after 60 days. This increase in biomass resulted from an increase in worker number and mean worker size. Access to carbohydrates also altered worker body size distributions. Finally, we found a negative relationship between worker number and size, suggesting a tradeoff in colony investment strategies. This tradeoff was more pronounced for colonies without access to carbohydrate resources. The monopolization of plant-based resources has been implicated in the ecological success of ants. Our results shed light on a possible mechanism for this success, and also have implications for the success of introduced species. In addition to increases in colony size, our results suggest that having access to plant-based carbohydrates can also result in larger workers that may have better individual fighting ability, and that can withstand greater temperature fluctuations and periods of food deprivation.

Effects of carbohydrate supplements on exercise-induced menstrual dysfunction and ovarian subcellular structural changes in rats

BackgroundExercise-associated menstrual dysfunction (EAMD) is a common health problem in female athletes as a part of female athlete triad (FAT), a condition related to low energy availability. In this study, we explored the possibility that carbohydrate supplements can improve the status of EAMD and prevent exercise-induced ovarian injury in a FAT rat model. This research aimed to provide experimental evidence with regard to the relationship of energy intervention and EAMD. MethodsForty-five female Sprague–Dawley rats (2 months old) were randomly divided into five experimental groups: control group (C), 9-week exercise as model for EAMD (E), post-EAMD recovery group (R), oligosaccharide intervention group (O), and glucose intervention group (G). All rats were sacrificed at the end of 9 weeks. Serum samples were collected for measuring gonadotropin releasing hormone, follicle stimulating hormone, luteinizing hormone, 17β-estradiol and progesterone levels. The ovaries were taken for investigation of exercise- and carbohydrate-induced follicular subcellular structure changes. ResultsExercise induced irregular menstrual cycles and ovary subcellular structural damages, such as swollenness of mitochondria in rats from groups E and R. Both glucose and oligosaccharide supplements restored well-differentiated mitochondria in the ovarian follicular cells, and a significant improvement of endoplasmic reticulum and Golgi in swollenness in theca cells in groups O and G compared to groups C, E, and R. There was no difference in mitochondria subcellular structural changes between groups O and G. Group E showed attenuation of serum levels of 17β-estradiol and progesterone compared to C. There were no differences of 17β-estradiol serum levels among groups O, G, and R, while group G showed a lower level of progesterone than C. ConclusionFemale adult rats with 9-week continuous exercise can cause menstrual dysregulation as a model for EAMD. Post-EAMD intervention with glucose and oligosaccharide intake can normalize the menstrual cycle, restore the follicular subcellular structure, and reverse the exercise-induced reduction of ovary sex hormones. It suggests a positive feedback of hypothalamus–pituitary–ovary axis might be involved in the molecular mechanisms of energy intake in treating EAMD.

Effect Of Carbohydrate Supplementation During Intensified Training On Markers Of Immunity In Highly Trained Cyclists

Effect Of Carbohydrate Supplementation During Intensified Training On Markers Of Immunity In Highly Trained Cyclists

Effect of Carbohydrate Supplementation on the Physiological and Perceptual Responses to Prolonged Tennis Match Play

Carbohydrate supplementation is a popular nutritional practice used in tennis to enhance physical capacities, motor-skill performance, and delay fatigue. However, the effects of carbohydrate supplementation on physiological and perceptual responses during tennis match play are not established. This double blind, randomized, placebo (PLA)-controlled crossover study was designed to determine the influence of carbohydrate supplementation (0.5 g·kg·h) on glycemia, salivary hormones (cortisol and testosterone) concentration, salivary immunoglobulin A (IgA) concentration, and rating of perceived exertion (RPE) during 3 hours of tennis match play in 12 well-trained tennis players. The only significant difference between the 2 conditions was a lower salivary cortisol concentration postmatch in the carbohydrate trial (p < 0.05); however, there was a trend for higher glucose concentration (p = 0.06) and lower session-RPE (p = 0.08) after tennis match play in the carbohydrate condition, which may have some practical implications. There was no change in salivary testosterone, salivary IgA, and RPE responses during tennis match play between conditions (p > 0.05). These data indicate that carbohydrate ingestion during 3 hours of competitive tennis match play helps to maintain glycemia and attenuates the increase in salivary cortisol concentration compared with PLA.

Effects of carbohydrate supplementation on water quality, microbial dynamics and growth performance of giant tiger prawn (Penaeus monodon)

Biofloc technology based 45-day indoor growth trial was conducted to evaluate the effect of carbohydrate (CHO), molasses supplementation on two developmental stages viz, juvenile (J) and sub-adult (SA) of Penaeus monodon in zero-water exchange system. P. monodon juveniles (1.56 ± 0.04 g) and sub-adults (14.32 ± 0.22 g) were stocked in fibre-reinforced plastic tanks (1,000 L) with soil base. Carbohydrate supplementation significantly reduced (p < 0.05) the total ammonia nitrogen (TAN), nitrite-N (NO2-N) and nitrate-N (NO3-N) over the time periods in sub-adult group. However, no significant difference in TAN and NO2-N was observed in juvenile-based treatments. Supplementation of carbohydrate significantly increased (p < 0.05) the water and soil total heterotrophic bacterial (THB) count in both juvenile and sub-adults. Despite increase in total Vibrio count (TVC), lower TVC/THB % was noticed in the water column of J + CHO (0.82) and SA + CHO (0.73) compared to control groups, J − CHO (1.48) and SA − CHO (1.21). Supplementation of carbohydrate increased the final body weight in J + CHO (6.51 ± 0.44 g) and SA + CHO (22.52 ± 0.98 g) compared with respective controls, J − CHO (5.05 ± 0.45 g) and SA − CHO (20.00 ± 0.33 g). Similarly, significantly lower (p < 0.05) feed conversion ratio and better protein efficiency ratio were recorded in carbohydrate-supplemented juvenile and sub-adults treatment groups. The present study demonstrates that supplementation of carbohydrate reduced the nitrogenous metabolites and significantly enhanced the growth performance of juvenile and sub-adult of P. monodon.

Efeitos da suplementação carboidratada e de diferentes tipos de treinamento físico sobre as concentrações de células sanguíneas

INTRODUÇÃO: A participação dos atletas em sessões de exercício intenso e prolongado pode fazer declinar o número circulante e a capacidade funcional dos leucócitos. Por outro lado, o consumo de uma solução carboidratada pode atenuar os efeitos imunossupressivos do exercício. OBJETIVO: Verificar os efeitos do exercício aeróbio e anaeróbio, além da suplementação carboidratada sobre as concentrações sanguíneas da contagem total e diferencial de leucócitos, hemoglobina e glicose sérica de ratos Wistar. MÉTODOS: Sessenta e nove Ratos machos Wistar (60 dias) foram divididos em seis grupos: sedentários não suplementados (n = 12) e suplementados (n = 12); treinados em estado estável máximo de lactato (EEML) não suplementados (n = 11) e suplementados (n = 11); treinados em alta intensidade não suplementados (n = 12) e suplementados (n = 11). O protocolo de treinamento consistiu de oito semanas de natação em padrão contínuo em EEML (60 min.dia-1) ou intermitente (dois períodos de 30 minutos, com intervalo de 10 minutos), com sobrecargas correspondentes a 5% e 10% do peso corporal, respectivamente. Durante 37 dias os animais foram suplementados com uma dose diária de 0,48 g.kg-1 de maltodextrina dissolvida em água ou receberam água pura. RESULTADOS: Não houve efeito da suplementação carboidratada e dos dois tipos de treinamento nas concentrações de leucócitos sanguíneos. O exercício anaeróbio (p = 0,04) e o uso da maltodextrina (p = 0,003) proporcionaram elevações nas concentrações de hemoglobinas sanguíneas, enquanto o exercício aeróbio ocasionou aumento na concentração da glicose sérica (p < 0,02). CONCLUSÃO: Os diferentes tipos de exercícios não estiveram envolvidos com leucopenia, hipoglicemia ou anemia que poderiam levar a fadiga muscular precoce e queda do desempenho.

Effects of Carbohydrate Supplementation on Force Output and Time to Exhaustion During Static Leg Contractions Superimposed with Electromyostimulation

The purpose of this study was to investigate the effects of carbohydrate ingestion on force output and time to exhaustion using single leg static contractions superimposed with brief periods of electromyostimulation. Six trained male subjects participated in a randomized, counterbalanced, double-blind study. The subjects were randomly assigned to placebo (PL) or carbohydrate (CHO). The subjects in CHO consumed 1 g of carbohydrate per kilogram of body mass loading dose and 0.17 g of carbohydrate per kilogram of body mass every 6 minutes during the exercise protocol. The PL received an equal volume of a solution made of saccharin and aspartame. The exercise protocol consisted of repeated 20-second static contractions of quadriceps muscle at 50% maximal voluntary contraction followed by 40-second rest until failure occurred. Importantly, the force output during quadriceps maximal voluntary contraction strength with superimposed electromyostimulation was measured in the beginning and every 5 minutes during the last 3 seconds of static contractions throughout the exercise protocol. Venous blood samples were taken preexercise, immediately postexercise, and at 5 minutes postexercise and analyzed for blood lactate. Our results indicate that time to exhaustion (PL = 16.0 ± 8.1 minutes; CHO = 29.0 ± 13.1 minutes) and force output (PL = 3,638.7 ± 524.5 N; CHO = 5,540.1 ± 726.1 N) were significantly higher (p < 0.05) in CHO compared with that in PL. Data suggest that carbohydrate ingestion before and during static muscle contractions can increase force output and increase time to exhaustion. Therefore, our data suggest that carbohydrate supplementation before and during resistance exercise might help increase the training volume of athletes.

Carbohydrate supplementation delays DNA damage in elite runners during intensive microcycle training

The aim of this study was to evaluate the effect of carbohydrate supplementation on free plasma DNA and conventional markers of training and tissue damage in long-distance runners undergoing an overload training program. Twenty-four male runners were randomly assigned to two groups (CHO group and control group). The participants were submitted to an overload training program (days 1-8), followed by a high-intensity intermittent running protocol (10 × 800 m) on day 9. The runners received maltodextrin solution (CHO group) or zero energy placebo solution as the control equivalent before, during, and after this protocol. After 8 days of intensive training, baseline LDH levels remained constant in the CHO group (before: 449.1 ± 18.2, after: 474.3 ± 22.8 U/L) and increased in the control group (from 413.5 ± 23.0 to 501.8 ± 24.1 U/L, p < 0.05). On day 9, LDH concentrations were lower in the CHO group (509.2 ± 23.1 U/L) than in the control group (643.3 ± 32.9 U/L, p < 0.01) post-intermittent running. Carbohydrate ingestion attenuated the increase of free plasma DNA post-intermittent running (48,240.3 ± 5,431.8 alleles/mL) when compared to the control group (73,751.8 ± 11,546.6 alleles/mL, p < 0.01). Leukocyte counts were lower in the CHO group than in the control group post-intermittent running (9.1 ± 0.1 vs. 12.2 ± 0.7 cells/µL; p < 0.01) and at 80 min of recovery (10.6 ± 0.1 vs. 13.9 ± 1.1 cells/µL; p < 0.01). Cortisol levels were positively correlated with free plasma DNA, leukocytes, and LDH (all r > 0.4 and p < 0.001). The results showed that ingestion of a carbohydrate beverage resulted in less DNA damage and attenuated the acute post-exercise inflammation response, providing better recovery during intense training.

Effects of carbohydrate supplementation on competitive runners undergoing overload training followed by a session of intermittent exercise

This study evaluated the effects of a micro cycle of overload training (1st-8th day) on metabolic and hormonal responses in male runners with or without carbohydrate supplementation and investigated the cumulative effects of this period on a session of intermittent high-intensity running and maximum-performance-test (9th day). The participants were 24 male runners divided into two groups, receiving 61% of their energy intake as CHO (carbohydrate-group) and 54% in the control-group (CON). The testosterone was higher for the CHO than the CON group after the overload training (694.0 +/- 54.6 vs. CON 610.8 +/- 47.9 pmol/l). On the ninth day participants performed 10 x 800 m at mean 3 km velocity. An all-out 1000 m running was performed before and after the 10 x 800 m. Before, during, and after this protocol, the runners received solution containing CHO or the CON equivalent. The performance on 800 m series did not differ in either group between the first and last series of 800 m, but for the all-out 1000 m test the performance decrement was lower for CHO group (5.3 +/- 1.0 vs. 10.6 +/- 1.3%). The cortisol concentrations were lower in the CHO group in relation to CON group (22.4 +/- 0.9 vs. 27.6 +/- 1.4 pmol/l) and the IGF1/IGFBP3 ratio increased 12.7% in the CHO group. During recovery, blood glucose concentrations remained higher in the CHO group in comparison with the CON group. It was concluded that CHO supplementation possibly attenuated the suppression of the hypothalamic-pituitary-gonadal axis and resulted in less catabolic stress, and thus improved running performance.

Effect of carbohydrate supplementation on tennis match play performance

Purpose: The aim of the present study was to assess the effect of a carbohydrate (CHO) (or placebo-PLA) beverage ingestion on ratings of perceived exertion (RPE), heart responses and tennis match play performance.

Effects of Carbohydrate Supplementation on the RPE-Blood Lactate Relationship

To examine the effects of carbohydrate (CHO) ingestion on the RPE-blood lactate relationship during incremental and constant-effort exercise. Six male and three female subjects (mean age = 27.2 +/- 8.2 yr, height [ht] = 174.5 +/- 13.5 cm, weight [wt] = 68.9 +/- 12.5 kg, body fat = 18.5 +/- 8.3%), completed two incremental cycling lactate threshold (LT)/(.)VO2peak tests followed by two 45-min production trials. Two hundred and forty milliliters of either carbohydrate or placebo (PL) was ingested before and every 15 min during exercise. No differences were observed between conditions at LT, 2.5 and 4.0 mM, and peak. Within the CHO condition: V O2 = 25.0, 32.6, 37.5, 47.2 mL x kg x min(-1); power output = 123.3, 170.7, 200.1, 241.7 W; RPE = 12.8, 15.4, 17.2, 19.3; and HR = 137.4, 156.8, 168.7, 187.7 beats x min(-1) at LT, 2.5 mM, 4.0 mM, and peak, respectively. Within PL: V O2 = 24.7, 32.5, 36.8, 45.7 mL x kg x min(-1); power output = 130.0, 175.4, 201.9, 240.0 W; RPE = 12.1, 15.0, 17.0, 19.3; and HR = 134.9, 157.9, 169.6, 187.2 beats x min(-1), respectively. In the CHO condition, blood glucose was higher (P < 0.001), and a trend was observed for lower RPE over time (P = 0.07). During the production trials (RPE of 16) in the CHO condition, higher blood glucose area under the curve (AUC) (PL: 204.1 +/- 79.3 mM; CHO: 220.6 +/- 18.5 mM; P = 0.039) and a trend for greater total work (PL: 448.5 +/- 73.8 kJ; CHO: 470.5 +/- 65.6 kJ; P = 0.089) were observed. We conclude that 1) CHO ingestion does not alter the blood lactate-RPE relationship during incremental LT/(.)VO2peak cycling; and 2) carbohydrate supplementation during exercise, eliciting high RPE, may increase work output during training sessions.

Effects Of Carbohydrate Supplementation On The Ratings Of Perceived Exertion- Blood Lactate Relationship

PURPOSE: To examine the effects of carbohydrate (CHO) ingestion on the RPE-blood lactate relationship during incremental and constant effort exercise. METHODS: Six male and three female subjects (mean age=27.2±8.2yrs; ht=174.5±13.5cm; wt=68.9±12.5kg; body fat=18.5±8.3%), completed two incremental cycling LT/VO2peak tests followed by two 45-minute production trials. Either ∼240 ml of a carbohydrate or placebo (PL) was ingested before and every 15 min during exercise. RESULTS: No differences were observed between conditions at LT, 2.5 and 4.0 mM and peak. Within the CHO condition: VO2= 25.0, 32.6, 37.5, 47.2 ml/kg*min-1; poweroutput=123.3, 170.7, 200.1, 241.7 watts; RPE= 12.8, 15.4, 17.2, 19.3; and HR= 137.4, 156.8, 168.7, 187.7 bpm at LT, 2.5mM, 4.0mM and peak, respectively. Within PL VO2= 24.7, 32.5, 36.8,45.7 ml/kg*min-1; power output= 130.0, 175.4, 201.9, 240.0 watts; RPE= 12.1, 15.0, 17.0, 19.3;and HR= 134.9, 157.9, 169.6, 187.2 bpm, respectively. In the CHO condition blood glucose was higher (P < 0.001) and a trend was observed for lower RPE over time (P = 0.07). During the production trials (RPE of 16) in the CHO condition higher blood glucose area under the curve (AUC) (PL: 204.1±79.3; CHO: 220.6±18.5 mM, P=0.039) and a trend for greater total work (PL: 448.5±73.8; CHO 470.5±65.6 kJ, P=0.089) were observed. CONCLUSION: We conclude that: 1) CHO ingestion does not alter the blood lactate-RPE relationship during incremental LT/VO2peak cycling; and 2) carbohydrate supplementation during exercise eliciting high RPE may increase work output during training sessions.

Effects of Carbohydrate Supplementation on Changes in Cognitive Function during Prolonged Exercise in the Heat.

PURPOSE: The purpose of this investigation was to determine if cognitive function is influenced by exercise in the heat and carbohydrate supplementation. METHODS: Eight males (age=23+1 years; VO2peak=51.3+1.4 ml.kg−1.min−1; weight=69.1+2.7 kg, ventilatory threshold=69.3+2.7% of VO2peak) completed 4 exercise trials to volitional fatigue. During each trial subjects cycled at 60% of ventilatory threshold. Subjects exercised in a normal (∼22°C & 50% humidity) (NORM) or hot (∼35°C & 70% humidity) (HOT) environment. Every thirty minutes during exercise subjects drank 5 ml.kg−1 of body weight of either a 6% carbohydrate beverage (CHO) or a water placebo (PLAC) indistinguishable in color and taste. Subjects completed a cognitive assessment battery (CAB) before, after 1 hour of exercise, and immediately after fatigue. The CAB included tests assessing grammatical reasoning (GR), code substitution (CS), math processing (MP), and tapping (TP). RESULTS: The percent correct in GR was affected by the environmental conditioning (p=0.032). For example, percent correct GR task during NORM (NORM PLAC=89.9+3.2%; NORM CHO=88.1+3.5%) was greater at fatigue than during HOT (HOT PLAC=82.1+11.1%; HOT CHO=82.3+7.2%). The percent correct in MP was affected by both the drink (p=0.031) and environmental (p=0.024) condition. For example, percent correct in MP during NORM CHO (91.8+2.1%) after 60 minutes of exercise was greater than all other conditions (NORM PLAC=83.8+1.2%; HOT PLAC=81.7+7.2; HOT CHO=86.6+61.%). Percent correct in CS was similarly affected by both the drink (p<0.001) and environmental (p=0.001) condition. Reaction time in GR was faster at fatigue during NORM CHO (2.37+0.54 sec) as compared to NORM PLAC (2.59+0.22 sec) (p=0.007); however, no differences were seen at this time during HOT. Similar findings were present in reaction time at fatigue in MP (NORM CHO=1.12+0.14 sec; NORM PLAC=1.33+0.03 sec) (p=0.001). No differences were observed in reaction time in CS and no differences were observed in TP for any measure. CONCLUSIONS: The results of this investigation suggest that cognitive function is negatively affected by prolonged exercise in the heat; however, some of these deleterious effects can be attenuated by CHO supplementation. Supported by the Gatorade Sport Science Institute

The Effects of Carbohydrate Supplementation on Fatigue during Intermittent Cycling

The Effects of Carbohydrate Supplementation on Fatigue during Intermittent Cycling

Effect of Carbohydrate Supplementation on Physical, Skilled and Cognitive Performance During a Simulated Volleyball Protocol

PURPOSE: To investigate the effect of ingestion of a carbohydrate-electrolyte beverage on exercise performance during simulated volleyball. METHODS: Ten NCAA DIII volleyball players took part in 2 counterbalanced exercise sessions where a sports drink (6% carbohydrate-electrolyte, CHO) or flavored placebo (PLA) was provided. Athletes ingested 20 ml/kg (35.9±4.1 g carbohydrate/hr) prior to & during exercise. A high-intensity, "stop-and-go" exercise protocol (125 min: 10-min warm-up, four 23-min games, four 2½-min breaks between games, and a 6-min "game 5") previously designed to closely mimic the physical & skilled demands of a competitive volleyball match was utilized. Each "game" included: 27 front & 27 back row rallies (2.9-27s), 50 breaks between rallies (16.2-18.9s), and three 47s time-outs (work:rest = 1:3.3). During rallies, athletes viewed instructions on a screen and performed timed locomotive tasks (shuffling, walking, jogging, sprinting) as well as volleyball specific skills. Each skill performed was scored for accuracy. Also, a timed "hopscotch" performance task was completed once/game. "Game 5" was maximum-intensity and included: serves, 12m timed shuttles, attacks, block jumps and passes. Cognitive testing (POMS, concentration grid, memory recall) was undertaken between "games". RESULTS: 1332±121 ml of fluid was ingested in each trial. Blood glucose (115.7±8.5 vs 101.0±3.0 mg/dl) and lactate were higher in CHO compared to PLA. Heart rate (162.2±4.0 bpm) & RPE (14.67±0.30) increased in game 5, but were not different between trials. There were no differences between trials for any skilled performance or cognitive tasks. No net change in body weight occurred in either trial, indicating similar sweat rates and ingested fluid volumes. Hopscotch task times & errors appeared to improve with CHO (p>0.05). CONCLUSION: CHO ingestion increased glucose & lactate, but had little effect on volleyball performance. The lack of performance changes with CHO may be due to: high variability in volleyball skill performance, the simulated protocol didn't adequately mimic an actual volleyball match (no competition/motivation) or the physical demands of volleyball are not intense enough to benefit from CHO supplementation for the duration of a match. Supported by the Gatorade Sports Science Institute.

Effect of carbohydrate supplementation provided through drinking water during feed withdrawal on meat and liver colours in broilers

BACKGROUND:The effect of saccarose supplementation provided through drinking water during feed withdrawal on meat and liver colour was investigated in a total of 50 broilers (five floor pens with 10 broilers) at 43 days. Treatments consisted of: (1) full-fed control broilers fed the standard broiler diet and water for the full 10 h (control); (2) fasted broilers receiving only water (FW); (3) 1 g (0.01SW); (4) 2 g (0.02SW); and (5) 3 g (0.03SW) saccarose L−1 supplemented water for the 10 h. The CIE colour values representing lightness (L*), redness (a*), and yellowness (b*) were measured on raw livers, breast and thigh meats. RESULTS:Full-fed broilers had lower dressing percentage, higher abdominal fat and liver yield and lighter thigh meat coloration than the FW birds (P < 0.05). The 0.02SW and 0.03SW resulted in live shrinks that were lower (P < 0.05) than those found in FW broilers. The 0.02SW and 0.03SW resulted in liver colours that were lighter than those found in FW and 0.01SW birds but darker than from control birds (P < 0.05). CONCLUSION:It was concluded that saccarose supplementation during feed withdrawal appears to have a measurable impact on live shrink, and lightness of liver and thigh meat colour in broilers. Copyright © 2007 Society of Chemical Industry

Biochemical Effects of Carbohydrate Supplementation in a Simulated Competition of Short Terrestrial Duathlon

The purpose of the present study was to investigate the biochemical effects of carbohydrate supplementation in a simulated competition of short terrestrial duathlon. Ten duathletes participated in a simulated competition of short terrestrial duathlon 30 minutes after the ingestion of a 6% (30 g/500 ml) maltodextrin solution (MALT) or a placebo (PLA). This solution was also ingested every 15 minutes during the competition (12 g/200 ml); and immediately after the competition (18 g/300 ml). Samples of blood were collected at 3 time points: 1) at rest 1 hour before the beginning of the competition; 2) during the competition (approximately 1 hour and 45 minutes after the 1st collection); 3) immediately after the competition. Blood was analyzed for blood glucose, lactate, insulin and cortisol. Significant differences were observed in relation to blood glucose levels between MALT and PLA in the post-competition phase. There was also a significant difference in the lactate levels observed between MALT and PLA during the competition phase. Similarly, a significant difference in the cortisol concentrations during and after the competition phases (MALT and PLA) were observed. We conclude that maltodextrin supplementation appears to be beneficial during short terrestrial duathlon competition as evidenced by biochemical markers.

Effects of acute carbohydrate supplementation during sessions of high-intensity intermittent exercise

The present study evaluated the acute effects of carbohydrate supplementation on heart rate (HR), rate of perceived exertion (RPE), metabolic and hormonal responses during and after sessions of high-intensity intermittent running exercise. Fifteen endurance runners (26 +/- 5 years, 64.5 +/- 4.9 kg) performed two sessions of intermittent exercise under carbohydrate (CHO) and placebo (PLA) ingestion. The sessions consisted of 12 x 800 m separated by intervals of 1 min 30 s at a mean velocity corresponding to the previously performed 3-km time trial. Both the CHO and PLA sessions were concluded within approximately 28 min. Blood glucose was significantly elevated in both sessions (123.9 +/- 13.2 mg dl(-1) on CHO and 147.2 +/- 16.3 mg dl(-1) on PLA) and mean blood lactate was significantly higher in the CHO (11.4 +/- 4.9 mmol l(-1)) than in the PLA condition (8.4 +/- 5.1 mmol l(-1)) (P < 0.05). The metabolic stress induced by the exercise model used was confirmed by the elevated HR (approximately 182 bpm) and RPE (approximately 18 on the 15-point Borg scale) for both conditions. No significant differences in plasma insulin, cortisol or free fatty acids were observed during exercise between the two trials. During the recovery period, free fatty acid and insulin concentrations were significantly lower in the CHO trial. Supplementation with CHO resulted in higher lactate associated with lipolytic suppression, but did not attenuate the cortisol, RPE or HR responses.