Cardio First if You Want to Leave the Gym More "Anabolic" Than You Were When You Came in? Study Finds Higher Testosterone Levels & Identical Strength Performance

The "North American Wife Carrying Championship" is probably not what researchers are talking about when they talk about "concomitant exercise"... but when I come to think about it, I wonder what this does to the hormones of the carrier and the carried ;-)
Let me preface today's SuppVersity post with a reference to previous posts on exercise order and the statement that I don't believe this question is ever going to be settled. Let's take the greater leptin suppression in response to doing cardio first as an example (see "Cardio Before or After Weights?"). For someone with a <10% body fat level, this may in fact be a downside; after all, rock bottom leptin levels have also been implicated in the etiology of the Athlete Triad. For someone who has got quite a few pounds to lose before he or she can even claim having a flat tummy, on the other hand, there is hardly anything more beneficial than finally ridding him-/herself of chronic leptin overexpression and resistance.

Tell me who you are & I tell you how to train

Against that background, the first thing you should memorize about the recently published study by Cadore et al. from the Federal University of Rio Grande do Sul (Cadore. 2012) is the training status and physical fitness of the subjects, namely 19 young strength-trained men (mean 23.5 years), who were engaged in regular (4–6 times a week) and systematic training program for at least 3 months. Another important and significant information is the number of training sessions that were conducted. In this case of the 5 visits to the lab, the subjects trained on only two occasions, which means that they participated in both the
  • Table 1: Performance was identical regardless of the exercise order.
    strength training which lasted approximately 30 minutes and consisted of 3 sets of 8 repetitions at 75% of 1RM with 90 seconds of resting between bench press, squat, lat pull-down, and knee extensions (in the given order), and the 
  • aerobic training, which was performed for 30 minutes on a cycle ergometer at 75% of maximal heart rate
... only twice: Once, doing strength first (ST-AE), once doing aerobics first (AE-ST). The outcomes were, as you may have expected not fundamentally different, which is probably not the not least because the workload was 100% identical:
Figure 1: Total testosterone (nmol/L) and cortisol (nmol/dl) response to cardio first  (AE-ST) or cardio post (ST-AE); mind the axes (Cardore. 2012)
Still the data in figure 1 clearly shows that there is a definitive effect on "anabolism", or I should say the mainstream understanding of "anabolism" with a continuous(!) increase in testosterone in the AE-ST (cardio firs) group and no significant differences in the cortisol response. If you calculate the C/T ratios at the given time points, a purported critical value, when you leave the gym would clearly speak in favor of the AE-ST regimen (see figure 2), but ...
  • Figure 2: Increases in cortisol (top) and testosterone (bottom) and respective increases in lean body mass in response to a 12-week hypertrophy oriented resistance training program (West. 2012); cortisol to testosterone pre, mid and post the two 2x30 min workouts in study at hand (bottom) data expressed relative to group basline (Cardore. 2012)
    increases in testosterone after a workout have never been shown to increase gains in the long term; in fact the only long-term study I know of (and I have cited 1000x, already) showed that rather than - allegedly free - testosterone, higher cortisol levels correlate with increases in lean body mass (LBM, cf. figure 2, top + middle)
  • the study at hand does not allow any conclusions as far as the real world "anabolism" of the two protocols is concerned; with only one workout we would at least have had to have some protein uptake studies to make a prediction, but that was not part of the protocol
  • the increase in total testosterone in the ST-AE group from mid to post-exercise can - as the researchers point out - also be precipitated by the increased receptor binding and not a decrease in secretion. I have written about that in a precious article ("Anabolic workouts revisited"). While long arduous strength workouts decrease the number of androgen receptors, short and hard workouts have been shown to increase the numbers of receptors and also that strength training bout stimulates the acute increases in AR content (Willoughby. 2004). Cardore et al. are yet right to point out that "this hypothesis should be considered with caution and remains speculative" (Cardore. 2012)
So what? Is this yet another nice study of which the researchers claim that its "results are important" (Cardore. 2012), while disqualifying this statement in the previous sentence in which they talk about the "relationship between acute hormonal responses and chronic neuromuscular adaptations to strength training" (no wonder they did no cite the Burd study ;-)? I guess if we went only with the data we, the answer must be yes.

Making HIIT a Hit: Long intervals for increases in VO2 max even in already trained athletes, short intervals for overall fitness and fat loss. Rings a bell? Yep, that was part of the recommendations in part II of the "Making HIIT a Hit" article on the SuppVersity. Now add the weight and some "regenerative" light intensity steady state aerobics and you are set up for a leaner physique and above all a longer, healthier life.
If Cardore et al. do a follow up study on the long-term, real-world effects I will of course inform you. In the meantime I'd personally suggest that you keep to <3 cardio sessions per week. If possible either on seperate days or maybe using an AM - PM system if you want to combine strength and cardio training. Moreover you better keep away from the debilitating long cardio workouts in the non-existent "fat burning zone" and either perform real low level cardio for 40-60min (like walking on an incline treadmill; cycling is even more muscle sparing) and/or high intensity interval training (HIIT; cf. "Making HIIT a Hit - Part I / Part II"). If your goal is to lean out maximally or to minimize fat gains on a bulk, you won't get along without some type of cardio - plus the obligatory dietary tweaks, of course. But couldn't that hamper your gains? Well, training "in the zone" certainly will a moderate amount of HIIT and LISS (very light) are yet not going to hurt. In fact, if you are in this for health, there is no question that you do both cardio and weights - not necessarily in one workout, though.

References:
  • Cadore EL, Izquierdo M, Santos MG, Martins JB, Rodrigues Lhullier FL, Pinto RS, Silva RF, Kruel LF. Hormonal responses to concurrent strength and endurance training with different exercise orders. J Strength Cond Res. 2012 Dec;26(12):3281-8.
  • West DW, Phillips SM. Associations of exercise-induced hormone profiles and gains in strength and hypertrophy in a large cohort after weight training. Eur J Appl Physiol. 2012 Jul;112(7):2693-702. 
  • Willoughby, DS and Taylor, L. Effects of sequential bouts of resistance exercise on androgen receptor expression Med Sci Sports Exerc. 2004; 36:1499–1506.