Effect of Glycemic Index of a Pre-exercise Meal on Endurance Exercise Performance : A Systematic Review and Meta-analysis
Burdon, Catriona A. ; Spronk, Inge ; Cheng, Hoi Lun ; O’Connor, Helen T. - \ 2017
Sports Medicine 47 (2017)6. - ISSN 0112-1642 - p. 1087 - 1101.
Background: Low glycemic index (GI) pre-exercise meals may enhance endurance performance by maintaining euglycemia and altering fuel utilization. However, evidence for performance benefits is equivocal. Objective: To evaluate the effect of a low GI (LGI) versus a high GI (HGI) pre-exercise meal on endurance performance using meta-analyses. Methods: Data sources included MEDLINE, SPORTDiscus, AUSPORT, AusportMed, Web of Science, and Scopus. Eligibility criteria were randomized, crossover trials with an endurance exercise (≥60 min) component, e.g., time trial (TT), time to exhaustion (TTE) test, or submaximal bout followed by TT or TTE. Participants were healthy, active individuals aged ≥16 years. Interventions included a LGI (≤55) and HGI (≥70) meal ingested 30–240 min before exercise. Study quality was assessed using an adapted version of the validated Downs and Black tool. Effect size (ES) and 95 % confidence interval were calculated for each study and pooled according to performance test type and whether exogenous carbohydrate (CHO) was given during exercise. Potential effect modifiers including exercise duration, pre-exercise meal timing, glycemic load (GL), and fitness were assessed using meta-regression. Results: The search netted 3431 citations with 19 studies eligible for inclusion (totaling 188 participants; 91 % male; VO2max: >50 ml/kg/min). Meals with 0.18–2 g CHO/kg body mass, and a mean GI and glycemic load of 82 (GL: 72) and 35 (GL: 32) for HGI and LGI, respectively, were given between 30 and 210 min before exercise. All test types without CHO ingestion during exercise showed slightly improved performance with LGI, but no significant pooled effects were observed (ES: −0.17 to −0.36; p > 0.05). Studies where exogenous CHO was ingested during exercise showed conflicting results (ES: −0.67 to 0.11; p = 0.04 to 0.94). No significant relationship was observed with any of the effect modifiers (p > 0.05). No consistent metabolic responses (glucose, insulin, lactate, respiratory exchange ratio) during exercise were observed with either meal type. Limitations: There were small numbers of studies within each exercise testing protocol and limited statistical power within studies. Pre-exercise meal timing, GL, meal composition and participant fitness varied across studies, limiting the capacity to assess the influence of these factors on study outcomes. Conclusion: There was no clear benefit of consuming a LGI pre-exercise meal for endurance performance regardless of carbohydrate ingestion during exercise.
Relationship between general nutrition knowledge and dietary quality in elite athletes
Spronk, Inge ; Heaney, Susan E. ; Prvan, Tania ; O'Connor, Helen T. - \ 2015
International Journal of Sport Nutrition & Exercise Metabolism 25 (2015)3. - ISSN 1526-484X - p. 243 - 251.
Nutrition assessment - Nutrition knowledge - Nutritional status - Sport nutrition
This study investigated the association between general nutrition knowledge and dietary quality in a convenience sample of athletes (≥ state level) recruited from four Australian State Sport Institutes. General nutrition knowledge was measured by the validated General Nutrition Knowledge Questionnaire and diet quality by an adapted version of the Australian Recommended Food Score (A-ARFS) calculated from food frequency questionnaire data. Analysis of variance and linear modeling were used to assess relationships between variables. Data: mean (Standard Deviation). A total of 101 athletes (Males: 37; Females: 64), 18.6 (4.6) years were recruited mainly from team sports (72.0%). Females scored higher than males for both nutrition knowledge (Females: 59.9%; Males: 55.6%; p = .017) and total A-ARFS (Females: 54.2% Males: 49.4%; p = .016). There was no significant influence of age, level of education, athletic caliber or team/individual sport participation on nutrition knowledge or total A-ARFS. However, athletes engaged in previous dietetic consultation had significantly higher nutrition knowledge (61.6% vs. 56.6%; p = .034) but not total A-ARFS (53.6% vs. 52.0%; p = .466). Nutrition knowledge was weakly but positively associated with total A-ARFS (r = .261, p= .008) and A-ARFS vegetable subgroup (r = .252, p = .024) independently explaining 6.8% and 5.1% of the variance respectively. Gender independently explained 5.6% of the variance in nutrition knowledge (p= .017) and 6.7% in total A-ARFS (p = .016). Higher nutrition knowledge and female gender were weakly but positively associated with better diet quality. Given the importance of nutrition to health and optimal sports performance, intervention to improve nutrition knowledge and healthy eating is recommended, especially for young male athletes.
Relationship between nutrition knowledge and dietary intake
Spronk, Inge ; Kullen, Charina ; Burdon, Catriona ; O'Connor, Helen - \ 2014
The British journal of nutrition 111 (2014)10. - ISSN 0007-1145 - p. 1713 - 1726.
Dietary intakes - Nutrition knowledge - Systematic reviews
The present systematic review examined the relationship between nutrition knowledge and dietary intake in adults (mean age ≥Â 18 years). Relevant databases were searched from the earliest record until November 2012. Search terms included: nutrition; diet or food knowledge and energy intake; feeding behaviour; diet; eating; nutrient or food intake or consumption. Included studies were original research articles that used instruments providing quantitative assessment of both nutrition knowledge and dietary intake and their statistical association. The initial search netted 1Â 193Â 393 potentially relevant articles, of which twenty-nine were eligible for inclusion. Most of them were conducted in community populations (n 22) with fewer (n 7) in athletic populations. Due to the heterogeneity of methods used to assess nutrition knowledge and dietary intake, a meta-analysis was not possible. The majority of the studies (65·5Â %: community 63·6Â %; athletic 71·4Â %) reported significant, positive, but weak (r<Â 0·5) associations between higher nutrition knowledge and dietary intake, most often a higher intake of fruit and vegetables. However, study quality ranged widely and participant representation from lower socio-economic status was limited, with most participants being tertiary educated and female. Well-designed studies using validated methodologies are needed to clarify the relationship between nutrition knowledge and dietary intake. Diet quality scores or indices that aim to evaluate compliance to dietary guidelines may be particularly valuable for assessing the relationship between nutrition knowledge and dietary intake. Nutrition knowledge is an integral component of health literacy and as low health literacy is associated with poor health outcomes, contemporary, high-quality research is needed to inform community nutrition education and public health policy.
Binding of the AVR4 elicitor of Cladosporium fulvum to chitotriose units is facilitated by positive allosteric protein-protein interactions
Burg, H.A. van den; Spronk, C.A.E.M. ; Boeren, S. ; Kennedy, M.A. ; Vissers, J.P.C. ; Vuister, G.W. ; Wit, P.J.G.M. de; Vervoort, J.J.M. - \ 2004
Journal of Biological Chemistry 279 (2004)16. - ISSN 0021-9258 - p. 16786 - 16796.
wheat-germ-agglutinin - urtica-dioica agglutinin - pathogenesis-related proteins - nuclear magnetic-resonance - n-acetylglucosamine - carbohydrate interactions - antifungal activity - cf-4-mediated resistance - conformational-analysis - tobacco chitinases
The attack of fungal cell walls by plant chitinases is an important plant defense response to fungal infection. Anti-fungal activity of plant chitinases is largely restricted to chitinases that contain a noncatalytic, plant-specific chitin-binding domain (ChBD) ( also called Hevein domain). Current data confirm that the race-specific elicitor AVR4 of the tomato pathogen Cladosporium fulvum can protect fungi against plant chitinases, which is based on the presence of a novel type of ChBD in AVR4 that was first identified in invertebrates. Although these two classes of ChBDs ( Hevein and invertebrate) are sequentially unrelated, they share structural homology. Here, we show that the chitin-binding sites of these two classes of ChBDs have different topologies and characteristics. The K-D, DeltaH, and DeltaS values obtained for the interaction between AVR4 and chito-oligomers are comparable with those obtained for Hevein. However, the binding site of AVR4 is larger than that of Hevein, i.e. AVR4 interacts strictly with chitotriose, whereas Hevein can also interact with the monomer N-acetylglucosamine. Moreover, binding of additional AVR4 molecules to chitin occurs through positive cooperative protein-protein interactions. By this mechanism AVR4 is likely to effectively shield chitin on the fungal cell wall, preventing the cell wall from being degraded by plant chitinases.
|A chitin-binding domain in the AVR4 elicitor of Cladosporium fulvum protects fungi against chitinase
Burg, H.A. van den; Harrison, S. ; Spronk, C.A.E.M. ; Westerink, N. ; Boeren, J.A. ; Joosten, M.H.A.J. ; Wit, P.J.G.M. de; Vervoort, J.J.M. - \ 2003
In: Volume of Abstracts: 11-th International Congress on Molecular Plant-Microbe Interactions, St.-Petersburg, Russia, 18-26 July 2003 St.-Petersburg, Russia : All-Russia Research Institute for Agricultural Microbiology - p. 250 - 250.
|Actief en constructief leren in het agrarisch onderwijs
Alaké-Tuenter, E. ; Biemans, H.J.A. ; Jong, F.P.C.M. de; Jongmans, C.T. ; Lazonder, A.W. ; Spronk, H.J. ; Wopereis, I.G.J.H. - \ 1999
Agrarisch Onderwijs 41 (1999)14. - ISSN 0925-837X - p. 26 - 27.
onderwijsmethoden - docenten - leertheorie - innovaties - onderwijsvaardigheden - psychologie - leerlingen - studenten - agrarisch onderwijs - opleiding - onderwijsinstellingen - onderwijsorganisatie - teaching methods - teachers - learning theory - innovations - teaching skills - psychology - pupils - students - agricultural education - training - educational institutions - organization of education
Om het zelfstandig leervermogen van leerlingen te stimuleren is begeleiding van docenten en schoolleiders van belang. De deelnemende docenten coachen elkaar onder begeleiding van de onderzoekers
Structures of enzymically derived oligosaccharides from sorghum glucuronoarabinoxylan.
Verbruggen, M.A. ; Spronk, B.A. ; Schols, H.A. ; Beldman, G. ; Voragen, A.G.J. ; Thomas, J.R. ; Kamerling, J.P. ; Vliegenthart, J.F.G. - \ 1998
Carbohydrate Research : an international journal 306 (1998). - ISSN 0008-6215 - p. 265 - 274.
Dimers of a GFG hexasaccharide occur in apple fruit xyloglucan.
Spronk, B.A. ; Rademaker, G.J. ; Haverkamp, J. ; Thomas-Oates, E. ; Vincken, J.P. ; Voragen, A.G.J. ; Kamerling, J.P. ; Vliegenthart, J.F.G. - \ 1998
Carbohydrate Research : an international journal 305 (1998). - ISSN 0008-6215 - p. 233 - 242.
|Comparative plasmakinetics of furazolidone in 5 fish species at 3 temperatures.
Heijden, M.H.T. van der; Mengelers, M.J.B. ; Klasen, W.J.C. ; Spronk, M.F. ; Boon, J.H. - \ 1994
In: Abstract Int. Symp. Aquatic animal health. Seattle, Washington, USA (1994) W-23.6
|Extrinsic control of endocrines in the regulation of reproductive functions of insects
Wilde, J. de - \ 1982
In: Exogenous and endogenous influences on metabolic and neural control / Addink, A.D.F., Spronk, N.,