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Chicken legs, old man? Must have been too much antioxidants ;-)

If this is not your first waredownloadsoft article, you may have read about the potential negative effects of (high dose) anti-oxidant supplementation in previous waredownloadsoft articles about, or touching on the effects of hormesis, i.e. the beneficial effects of "good oxidative stress". Up to now I have yet often said that it is possible that this effect occurs mostly in people who can handle stress pretty well and thus have to hammer it to trigger a measurable adaptive response.

The elderly subjects in the latest study from the University of Agder in Norway (Bjornson. 2015), however, don't exactly belong to the group of people I was thinking about, when I phrased this hypothesis.

Table 1: Overview of the exercises the scientists did. The exercises were identical to a previous study in young individuals and the workout was designed to give large metabolic stress (i.e., oxidative stress) and the intention was to stimulate as much muscle growth as possible (Bjornson. 2015)

"The 12-week strength training program had an undulating periodized profile (Jiménez, 2009). The protocol included three full-body sessions per week, emphasizing free weight exercises where all the major muscle groups were included. Two of the sessions each week were “moderate” (8–10 rep, with 1 min rest between sets), and one varied between “heavy” (3–5 rep, with 2 min rest between sets) and “light” (13–15 rep, with 45 s rest between sets)” every second week. [...]  

The number of sets per exercise was increased progressively from 1 to 4 sets during the first 10 weeks, and then reduced with one set each of the last 2 weeks of the intervention (tapering). 

The participants conducted one additional “warm-up” set at 50% of their target weight in each exercise before the main sets started. The last set of each exercise was performed with maximal number of repetition, and if the number of repetitions exceeded the sessions target repetitions, the load was adjusted for the next week’s sessions. Two experienced instructors supervised all strength training sessions and the loads were weekly adjusted" (Bjornson. 2015 | my emphases).

Hot or not? That could be a matter of health or ah... well almost death ;-)

Usually a "tea" is a hot beverage, right? No? Well, ok there's ice-tea, but even the coolest of all teas is initially brewed with hot, sometimes almost boiling water. A practice of which a recent study from the  Universidade Tecnológica Federal do Paraná in Brazil suggests that it may actually impair some of the beneficial effects of Baldo, White, Black and Mate tea.

How come? Well, in the study Vanessa de Carvalho Rodrigue, et al. conducted, it made a huge difference in terms of the total phenol and flavenoid content of the extracts (=the aformentioned teas) when the scientists used cold water instead of water that was 80°C "hot".
During the hot extraction procedure, a total of 2.0 g of the sample was extracted with 100 mL of water distilled at 80 °C. In contrast to how you would do it at home, though, the extraction process was propelled by stirring the glass for 450s (7:30 min). A similar procedure was used for the cold extract. The only differences were that (a) the extraction was done with 20 ml cold water and only 0.5 g of tea and (b) took 120 minutes during which the infusion was kept still, at room temperature (20–25 °C), and was stirred manually every 30 min (Damiani et al., 2014).

All extracts were filtered, transferred to Falcon tubes and immediately frozen at −20 °C (dark) for later analysis in order to prevent oxidation by light and oxygen.

Figure 1: Total phenol & flavenoid content tea after extraction with hot or cold water (de Carvalho Rodrigues. 2015).

The analysis yielded interesting results, because in contrast to what you may have expected not all hot water or extracts were inferior to their cold water counterparts. In the teas with generally lower phenol and flavenol intake, using the hot water to extract the active ingredients lead to significant (lemon grass and carqueja) increases of the total phenol and flavenoid content of the extracts.
What matters more than phenol and flavenol numbers, though, are (a - primarily) the antioxidant activity of the their sum (see Figure 2) and (b - secondarily) the presence of specific bioactive compounds like theobromine, chlorogenic acid or even caffeine (see Table 1).
Interestingly, significant differences were seen for the the often-tested DPPH+ (diphenylpicrylhydrazyl) radical scavenging activity only for Carqueja, Lemongrass and Mate (see Figure 2, left), and no significant effects were observed for the content of any of the bioactive agents. With the latter, the content varied, albeit not systematically and not with statistical significance.

Figure 2: Total antioxidant activity of the hot and cold extracts from various teas according to DPPH+ and TROLOX assays; sign. effects were observed only in the TROLOX assay (de Carvalho Rodrigues. 2015).

That's in contrast to the antioxidant activity in the ABTS˙+ or TROLOX test (Figure 2, right) where significant differences were observed for all teas. What is surprising, though is that these were not necessary in line with the total anti-oxidant activity which was increased in the cold extract of the Bodo tea, for example (it's anti-oxidant activity still was more than 50% lower).
References:

• de Carvalho Rodrigues, V., da Silva, M. V., dos Santos, A. R., Zielinski, A. A. F. and Haminiuk, C. W. I. (2015), Evaluation of hot and cold extraction of bioactive compounds in teas. International Journal of Food Science & Technology. doi: 10.1111/ijfs.12858