{"publication_id":"acbf1c12-fb9c-49dc-8bc1-caa5a119a8cf","content_hash":"sha256:2be08c16e36e91122da81bdc3cb28b7b7511551b71b4cc4770d721c9e2fc308c","nodes":[{"id":"acbf1c12-fb9c-49dc-8bc1-caa5a119a8cf","type":"publication","title":"Alpha memo: resveratrol blunts exercise training"},{"id":"claim_1","type":"claim","text":"Resveratrol may modestly reduce some exercise-induced cardiovascular gains in older men, but the evidence does not support claims of broadly negative or harmful effects."},{"id":"claim_2","type":"claim","text":"One-sentence alpha:** Resveratrol may modestly reduce some exercise-induced cardiovascular gains in older men, but the evidence does not support claims of broadly negative or harmful effects."},{"id":"claim_3","type":"claim","text":"Receipt 2:** \"Recent data do not provide evidence that resveratrol causes 'mainly negative' or 'adverse' effects on exercise training in humans\" (same journal, 2013) reanalyzes Gliemann et al. and finds that of ~45 variables examined, exercise training improved 12 variables and did not worsen others, concluding the original framing as \"adverse\" is not supported by the data shown."},{"id":"claim_4","type":"claim","text":"Why this is surprising:** The original paper's running head implies resveratrol counteracts exercise benefits, but the more granular re-examination suggests the blunting signal is narrow and may not generalize to a broader adverse-effect claim, meaning a single anchor (\"blunts\") can overstate the true effect direction."},{"id":"source_1","type":"source","study":"Resveratrol blunts the positive effects of exercise training on cardiovascular health in aged men","year":2013,"doi":"10.1113/jphysiol.2013.258061","url":"https://doi.org/10.1113/jphysiol.2013.258061","population":"not extracted","intervention_or_exposure":"not extracted","comparator":"not extracted","endpoint":"not extracted","effect":"not extracted","risk_of_bias":"not appraised in public sidecar","directness":"primary","excerpt":"Ageing is thought to be associated with decreased vascular function partly due to oxidative stress. Resveratrol is a polyphenol, which in animal studies has been shown to decrease atherosclerosis, and improve cardiovascular health and physical capacity, in part through its effects on Sirtuin 1 signalling and through an improved antioxidant capacity. We tested the hypothesis that resveratrol supplementation enhances training-induced improvements in cardiovascular health parameters in aged men. Twenty-seven healthy physically inactive aged men (age: 65 ± 1 years; body mass index: 25.4 ± 0.7 kg m(-2); mean arterial pressure (MAP): 95.8 ± 2.2 mmHg; maximal oxygen uptake: 2488 ± 72 ml O2 min(-1)) were randomized into 8 weeks of either daily intake of either 250 mg trans-resveratrol (n = 14) or of placebo (n = 13) concomitant with high-intensity exercise training. Exercise training led to a 45% greater (P < 0.05) increase in maximal oxygen uptake in the placebo group than in the resveratrol group and to a decrease in MAP in the placebo group only (-4.8 ± 1.7 mmHg; P < 0.05). The interstitial level of vasodilator prostacyclin was lower in the resveratrol than in the placebo group after training (980 ± 90 vs. 1174 ± 121 pg ml(-1); P < 0.02) and muscle thromboxane synthase was higher in the resveratrol group after training (P < 0.05). Resveratrol administration also abolished the positive effects of exercise on low-density lipoprotein, total cholesterol/high-density lipoprotein ratio and triglyceride concentrations in blood (P < 0.05). Resveratrol did not alter the effect of exercise training on the atherosclerosis marker vascular cell adhesion molecule 1 (VCAM-1). Sirtuin 1 protein levels were not affected by resveratrol supplementation. These findings indicate that, whereas exercise training effectively improves several cardiovascular health parameters in aged men, concomitant resveratrol supplementation can blunt these effects."},{"id":"source_2","type":"source","study":"Recent data do not provide evidence that resveratrol causes ‘mainly negative’ or ‘adverse’ effects on exercise training in humans","year":2013,"doi":"10.1113/jphysiol.2013.262956","url":"https://doi.org/10.1113/jphysiol.2013.262956","population":"not extracted","intervention_or_exposure":"not extracted","comparator":"not extracted","endpoint":"not extracted","effect":"not extracted","risk_of_bias":"not appraised in public sidecar","directness":"primary","excerpt":"It was with great interest that we read the article by Gliemann et al. (2013). The authors should be commended for using a solid study design to determine if resveratrol enhances the exercise response in humans as previously demonstrated in animal models. The authors concluded ‘exercise training effectively improves several cardiovascular health parameters in aged men, [but] resveratrol supplementation blunts most of these effects’. The slightly blunted response to exercise in a few dependent variables is embellished in the running head, entitled ‘adverse effects of resveratrol on cardiovascular health’. Such powerful wording suggests resveratrol actually counteracts the benefits of exercise training and is harmful, yet the results presented do not support such strong statements. The results presented reveal that, of ∼45 variables examined, exercise training improved 12 variables and did not influence 18 variables, independent of treatment group. Clearly, resveratrol does not blunt ‘most’ of the effects of exercise or produce ‘mainly negative’ effects, as the majority of comparisons revealed similar effects for resveratrol and placebo. Only two variables (TBX synthase and ET-B receptor) shifted in a potentially unfavourable direction within the resveratrol group, and ∼12 variables only showed statistical improvement in the placebo group, including some inter-related (e.g. low-density lipoprotein influences total cholesterol/high-density lipoprotein ratio) or nearly identical variables (e.g. three different methods of reporting ). Importantly, there were no post-training differences between groups for most of these, and it is not appropriate to interpret such results as statistical differences between groups (Gelman & Stern, 2006; Nieuwenhuis et al. 2011). This is exemplified using low-density lipoprotein cholesterol, where the placebo group decreased significantly (0.3 ± 0.2 mmol l−1), whereas the resveratrol group had a nearly identical, though non-significant within-group decrease (0.2 ± 0.2 mmol l−1). It is incorrect to declare that resveratrol ‘abolished’ this effect (Nieuwenhuis et al. 2011). Finally, certain aforementioned results may be due to the authors’ questionable use of the Student–Newman–Keuls post hoc test, where a risk for type I error (false significance) occurs with four comparisons per variable (Seaman et al. 1991; Drummond & Vowler, 2012)"}],"edges":[{"from":"acbf1c12-fb9c-49dc-8bc1-caa5a119a8cf","to":"claim_1","type":"contains_claim"},{"from":"acbf1c12-fb9c-49dc-8bc1-caa5a119a8cf","to":"claim_2","type":"contains_claim"},{"from":"acbf1c12-fb9c-49dc-8bc1-caa5a119a8cf","to":"claim_3","type":"contains_claim"},{"from":"acbf1c12-fb9c-49dc-8bc1-caa5a119a8cf","to":"claim_4","type":"contains_claim"}],"screening":{"identified":2,"screened":2,"excluded":0,"included":2,"included_or_retained":2,"flow":["identified","screened","excluded_with_reasons","included"],"wording":"2 candidate receipts retained after source retrieval, deduplication, and topic filtering. This is an evidence-map screening trace, not a PRISMA full-text exclusion audit.","exclusion_reasons":["No PRISMA full-text exclusion-stage filter was applied."]}}