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Dont obsess about "optimal" antioxidant contents, just eat your veggies!

Over the past couple of weeks, ... no actually over the past years I have repeatedly written about the concept of (mito-)hormesis and its consequences for the well-established, but not necessarily accurate free radical theory of aging (and for some people everything else). ROS, i.e. reactive oxygen species, have been established as an important signalling molecule that is - among other things - heavily involved in the insulin sensitizing effects of exercise. "Inflammation" makes muscles grow and burns body fat and the "what doesnt kill me makes me strong" principle appears to reign everywhere you look.
That being said, the latest study from the Institute of Health and Environmental Medicine in Tianjin, China, opens another "anti-antioxidant" Box of Pandora. One that puts a huge questionmark behind the implications of hundreds of thousands of scientific studies, when it says in its title, already: "No correlation is found for vegetables between antioxidant capacity and potential benefits in improving antioxidant function in aged rats"

"Skin of Grape Tomatoes Contains Max. Amount of Antioxidants" - You can find this and dozens of other daily updated SuppVersity Science News on www.facebook.com/SuppVersity

This is a title that may in fact change the way we look at study results like those of a recent study by Valdez-Morales, et al. (2014) investigating the "best" = highest antioxidant tomato, the results of which you are about to find among the ~20/day SuppVersity Facebook News @ www.facebook.com/SuppVersity - dont forget to like it, or youll miss out on the latest science news!

If the results of the study can be confirmed by an independent team for vegetables other than lotus root, rape or cucumber and if there is an identical mismatch between the in-vivo anti-oxidant capacity and the potential benefits in improving antioxidant function in (aged) humans.

This would be big and highly consequential news for nutrition experts, scientists and average Joes and Janes like you and me. Why? Well,...

• any ranking of "superfoods" that was based even partly on in vitro data derived with the good old ferric reducing antioxidant power (FRAP) assay would be invalid, ...
• every scientist who has been following up on "promising" data from FRAP assays would have been wasting his time, ...
• and you may have been eating all the wrong foods for years...

... hell no, as long as you ate your veggies over the past years, I wouldnt worry if you may have made a "suboptimal" selection (which would be different based on whatever new criteria you select).

Figure 1: FRAP value, vitamin C and vitamin E content and total amount phenolics in the powdered vegetables that were added to the rodent diets in the study at hand (Ji. 2014)

Honestly, Id hope that you didnt select your foods only based on the orthorexic principle of maximal antioxidant content, anyways. 

Never forget the three principles of veggie eating: Variety, seasonality, colorfulness

Against that background Id recommend you keep eating your lotus roots, if you like them, although, they have a significantly lower beneficial effect on SuperOxide Dismutase (SOD, a group of antioxidant enzymes) than rape and cucumber.

Figure 2: Serum markers of anti-oxidant status / oxidative damage after 6 weeks on the three experimental diets (Ji. 2014)

Moreover, if you look closely at the data in Figure 1+2, you will realize that lotus may suck at SOD and its ability to reduce hemolysis (the destruction of red blood cells), but will have the most profound beneficial effects on the levels of malondealdehyde (MDA), a marker of lipid oxidation, and the amount of plasma carbonyls, which have - just as in cellular regulation, aging, and disease (Levine. 2002). Just like their similarly radical cousins, carbonyls will thus play a dual role so that in the end, their reduction may not be beneficial in each and every case.
Reference: 

• Ji, Linlin, et al. "No correlation is found for vegetables between antioxidant capacity and potential benefits in improving antioxidant function in aged rats." Journal of Clinical Biochemistry and Nutrition 54.3 (2014): 198-203.
• Levine, Rodney L. "Carbonyl modified proteins in cellular regulation, aging, and disease^{2, 3}." Free Radical Biology and Medicine 32.9 (2002): 790-796.
• Valdez-Morales, Maribel, et al. "Phenolic content, and antioxidant and antimutagenic activities in tomato peel and seeds, and tomato by-products." Journal of Agricultural and Food Chemistry (2014). Accepted Manuscript.

Isnt HIIT for everyone? Study suggests: Effective- and usefulness of high intensity interval training depend on age and fitness level.

You will remember the two-part article serious about HIIT training "Making HIIT a HIT!" (Part I, Part II) I wrote back in 2012... you didnt well, although I would suggest you read it now, you will understand the idea of personalized HIIT training and there being no single optimal training regimen that works for everyone, anyways - right?

Good! Accordingly, you are not surprised that researchers from tie California State University San Marcos and the Griffith University at the Gold Coast in Queensland, Australia, teamed up to identify individual HIIT-responders and HIIT-non-responders.
The idea was to test whether there would be common denominators in those who do and those who dont respond with improvements in VO2max and lipid oxidation, as well as heart function and heart rate two commonly used modalities of interval training which have been previously-employed in the scientists lab.

"It was hypothesized that frequency of ‘‘non-responders’’ would be less than that typically reported after endurance training" (Astorino. 2014)

The ultimate goal obviously is the development of individualized exercise prescription which may help optimize responses to training and overall health status of various individuals.

In this particular case this meant determining whether the 20 habitually-active men and women who participated in part 1 of the study would show inter-individual as well as inter-group differences compared to the 20 non-obese sedentary women from part 2 of the study.

• In study 1, recreationally-active men and women underwent 2 wk of Wingate-based standardized interval treatment. At baseline and after completion of training, measures of VO2max, HR, and lipid oxidation were determined on separate days at least 24 h apart. Participants were required to maintain their habitual training status which was confirmed with a training log, and time of day was standardized within subjects across all trials. 

• SuppVersity Suggested Read: "More HMB Free Acid Science: Now Its Also Good For High Intensity Interval Training (HIIT) Says the Latest Sponsored Trial W/Out Calcium HMB Control in Young Men & Women" | read more

  In study 2, sedentary young women completed 12 wk of a more tolerable form of interval training at intensities equal to 60–80% or 80–90%Wmax, during which these variables were assessed at baseline and every 3 wk of the study over two separate sessions. They were required to refrain from additional physical activity other than activities of daily living outside of the study. Exercise was performed at approximately the same time of day (#60 min) within participants. In both studies, body composition was assessed pre- and post-training using waist:hip ratio and sum of threeskinfolds (chest, abdomen, thigh for men and triceps, suprailiac, and thigh for women) following standardized procedures.

The fact that we are comparing the short-term effects (4–6 per day at intensities = 200–300%Wmax) over a 2 wk period.) in healthy trained men and women to the long-term effects of 3 d/wk of interval training for 12 wk (six to ten 1 min bouts of cycling at work rates equal to 60–80%Wmax or 80–90%Wmax) in untrained, but still healthy women is allegedly not 100% logical and reduces the significance of the results.

Figure 1: Changes in HR and fat oxidation in trained (left, part 1) & untrained (right, part 2) individuals (Astorino. 2014)

The latter is yet only true for the inter-group, yet not the intra-group comparisons, of which the data in Figure 1 leaves no doubt that it confirms the existance of responsers and non-responders to both regimen:

"Frequency of improved fat oxidation was similar (60–65%) across regimens. Only one participant across both interventions showed nonresponse for all variables." (Astorino. 2014)

Interestingly, the vaseline values of VO2 max, exercise HR, respiratory exchange ratio, and body fat were significant predictors of adaptations to interval training:

• Positive predictors of increases in VO2max were low baseline fitness (difficult to improve whats already top) and high effort during the wingate test.
• Positive predictors of improved heart rate was a high age and a high baseline heart rate
• Positive predictors of increases in fat oxidation were a low baseline physical activity and a low age.

In other words, the short-term wingate protocol (intense HIIT) is most beneficial for the lazy ones, in general and helps the elderly with heart health, and the young with increasing their fat oxidation. For the low intensity chronic regimen things were similar: Body fatness was another non-fitness related positive predictor of increases in VO2max and improvements in heart rate and fat oxidation.
References:

• Astorino TA, Schubert MM (2014) Individual Responses to Completion of Short-Term and Chronic Interval Training: A Retrospective Study. PLoS ONE 9(5): e97638.