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Tampilkan postingan dengan label strength training. Tampilkan semua postingan

Jumat, 20 Mei 2016

Polarized Concomitant Training - Will it Help You Make Max. Gains & Improvements in Body Comp. W/ Strength+Cardio?

Polarized training? Find out more...
Does concurrent / concomitant training intensity distribution matter? Unless you're a first timer at the SuppVersity you will have read at least two or three previous articles of mine about studies investigating the effects of concurrent training, i.e. the combination of strength and cardio training, (i.e. concomitant training) here.

If you recall the results, you will know that previous research has demonstrated the influence of intensity distribution on strength endurance training adaptations.
You can learn more about the optimal exercise order at the SuppVersity

What's the Right Training 4 You?

Hypertrophy Blueprints

Fat Loss Support Blueprint

Strength Training Blueprints

Study: Over-training Exists

Recovering from the Athlete's Triad
You may also remember that no previous study has addressed the influence of "intensity distribution", i.e. the way intensity and volume are distributed across the training sessions, on the effectiveness of concurrent training (CT | see Figure 1). The goal was to prevent interference of the two types of training:
Figure 1: Training design of the experimental groups during the 8-week training period. Continuous-line and dotted-line circles represent the different training session modalities for the PT and TT groups, respectively. PT: polarized training group; TT: Traditional-based training group; BW: brisk walking; RM: repetition maximum; RNG: running; IST: intermittent sprint training (Varela-Sanz. 2016).
"Another problem which must be solved is the comparison of external training loads. Thus, our independent variable and focus was training intensity distribution with an equivalent total external load [...] of both training programs. A training group performed a combination of strength and endurance training aligned with the current ACSM recommendations of intensity distribution, while another group performed the same amount of external workload but with a polarized intensity distribution. Both ex. groups were evaluated before and after an 8-week training period (weekly training frequency of 3 days), and compared to a control group. To examine the effectiveness of the [...] training regimes, [...] physical (jump capacity, upper- and lower-body strength, running performance, and body composition), physiological (heart rate variability), and perceptual variables (rate of perceived exertion, training impulse, and feeling scale) were examined as dependent variables" (Varela-Sanz. 2016)
Thirty-one healthy sport science students (30 men, 5 women; all moderately active, but training less than 2 days per week apart from their academic activities which included a variable amount of PA on a daily basis) volunteered and were, after a 2-week familiarization phase (training thrice a week for two weeks), evaluated for resting heart rate variability (HRV), countermovement jump, bench press, half squat, and maximum aerobic speed (MAS).
I don't get it. How exactly did this "polarized training" work? Yes, the protocol was different from the one you may remember from Seiler et al. (2006) who tried to quantify training intensity distribution in elite endurance athletes. More specifically, subjects trained thrice a week (i.e. Monday, Wednesday, and Friday) for ~120 min each on Monday and Friday, and ~60 min on Wednesday. The training sessions on Mondays and Fridays consisted of cardiorespiratory exercise training (i.e. brisk walking or running) followed by resistance exercise training; meanwhile on Wednesdays participants only performed cardiorespiratory exercise training.

Each training session started with a standardized warm-up that consisted of 5 min of calisthenics followed by 5 min of brisk walking at 30% of the MAS. Before resistance exercises, participants also performed a specific warm-up that consisted of 2 sets of 8 repetitions of the resistance circuit they performed during the familiarization period with a OMNI-Scale perception of effort of 2-3. Cooling down exercises consisted of 2-3 sets of 15 s of stretching exercises of the muscle groups involved during the session. The exercises during the actual workout were bench press and half squat. Based on the conclusions of Simão et al., whose study had revealed that you will see greater gains on those exercises you do first in your workout, the order of resistance exercises was alternated each week. In that, the TT group performed 3-5 sets of 10-12 RM with 3 min of rest between sets. The PT group performed 3-5 sets of 5 RM on Mondays, and 2-4 sets of 15 RM on Fridays. The rest between sets was always 3 min. Resistance exercise workloads were equated.
All were then randomly distributed into either a traditional-based training group (TT; n=11; 65-75% of MAS, combined with 10-12RM), polarized training group (PT; n=10; 35-40% and 120% of MAS, combined with 5RM and 15RM), or control group (CG; n=10).
Figure 2: Relative changes in heart rate, jump height, peak power, bench press (1RM) and half squat (1RM) after 8 weeks of traditional (TT), polarized (PT) training or control (Varela-Sanz. 2016).
After 8 weeks of training (3 days.week-1), TT and PT exhibited similar improvements in MAS, bench press and half squat performances. No differences were observed between TT and PT groups for perceived loads. There were no changes in heart rate variability (HRV) for any group although TT exhibited a reduction in resting HR.
Figure 3: Effect sizes corresponding to the relative values in Figure 1 (Varela-Sanz. 2016).
What is worth mentioning, though, is that, compared to other groups, the PT group maintained jump capacity with an increment in body weight and BMI without changes in body fatness, in other words: they gained muscle, but also fat (see Figure in Bottom Line | body fat measured by skinfold "only").

There's one thing we didn't discuss yet: Was the polarized training maybe less taxing or more fun? The findings of the study at hand suggest that this was the case: TT and PT reported similar perceptions of effort, sensations, and internal load levels over the 8-week training period. Briefly, RPE and TRIMPS increased progressively along the 8-week training period. These perceptual levels demonstrated an increase in external load during the 3rd microcycle compared to the 1st and 2nd microcycles of each mesocycle. Thus, "the current findings suggest that different concurrent training regimes of equated loads could be similarly perceived by participants" (Varela-Sanz. 2016).
Effects on body composition; effect sizes and rel. (%) changes (Varela-Sanz. 2016).
Bottom line: The previously outlined observations lead the scientists to conclude that their funky polarization approach to concurrent training "induced similar improvements in physical fitness of physically-active individuals", but that "PT produced a lower interference for jumping capacity despite an increment in body weight, whereas TT induced greater bradycardia" (Varela-Sanz. 2016).

The fact that there were further benefits in terms of peak power, squat and bench press performance, but that those were not statistically significant (see Figure 2), however, is something the scientists don't mention in the abstract, even though these differences could become significant in the longer (>8 weeks) term.

A mistake? No, in view of the conflicting evidence from the calculated effect sizes (see Figure 3), it is absolutely correct to say that there were no meaningful inter-group differences in the most important parameters for most trainees, i.e. the bench press, half squat and the effects on body comp (see Figure on the right) | Comment!
References:
  • Seiler, K. Stephen, and Glenn Øvrevik Kjerland. "Quantifying training intensity distribution in elite endurance athletes: is there evidence for an “optimal” distribution?." Scandinavian journal of medicine & science in sports 16.1 (2006): 49-56.
  • Simao, Roberto, et al. "Exercise order in resistance training." Sports Medicine 42.3 (2012): 251-265.
  • Varela-Sanz, Adrián; Tuimil, José L.; Abreu, Laurinda; Boullosa, Daniel A. "Does concurrent training intensity distribution matter?" Journal of Strength & Conditioning Research: Post Acceptance: May 09, 2016 doi: 10.1519/JSC.0000000000001474.

Senin, 28 Desember 2015

"HIIT-ing it After Arm Workouts Will Ruin Your Gains", Study Says and Confuses Statistical and Practical Significance

Does this look as if sprinting would impair muscular development of arms or any other muscle? I mean, come on - look at the average sprinter: Many gymrats dream of the arms and overall muscular physique they have; no wonder that the data from the full-text shows a different picture than the abstract would suggest.
I have repeatedly written about combining strength and classic endurance training. With endurance first, endurance last and even endurance in-between the studies yielded often very different results in terms of what would be the optimal way to combine both. With a few exceptions in which resistance training was combined with crazy endurance training sessions, however, I've yet never written about nor seen compelling evidence for the often-heard claim that "cardio ruins your gains".

For HIIT, i.e. high-intensity interval training, a recent study from the Nippon Sport Science University does now claim, though, that my that combining HIIT and weight training may be a very bad idea, ... an idea that may in fact, just as the broscientific nightmare suggests "ruin your gains, bro!" Upon closer scrutiny, however, things appear less unambiguous than the abstract would have it...
You can learn more about the optimal exercise order at the SuppVersity

Before, After or In-Between?

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Cardio First for Anabolism?

Large Muscle Groups First?

Combine Cardio & Strength, Right

Cardio or Weights First? What the...
The purpose of the study was to examine whether or not lower limb sprint interval training following arm resistance training influences training response of arm muscle strength and hypertrophy. Or in short: Will doing HIIT sprints immediately after an arm workout ruin the strength and strength gains you've primed before? 
Figure 1: According to the study, you better don't do HIIT sprint training after an intense arm workout if you don't want to ruin the strength and size gains you "primed" with curls and co (photo from Kikuchi. 2015)
The subjects, twenty previously only lightly trained men, were divided into resistance a training group (RT, n=6) and concurrent training group (CT, n=6).
  • The RT program was designed to induce muscular hypertrophy (3 sets x 10 repetitions (reps) at 80% 1 repetition maximum [1RM] of arm curl exercise), and was performed in an 8-week training schedule carried out 3 times per week on nonconsecutive days. 
  • Subjects assigned to the CT group performed identical protocols as strength training (ST) and modified sprint interval training (4 sets of 30-s maximal effort, separated in 4m 30-s rest intervals) on the same day. 
The relevant study outcomes the researchers evaluated were the changes in maximal oxygen consumption (VO2max), muscle cross-sectional area (CSA), and 1RM that were measured before and after the 6-week study.
Figure 1: Relative changes in VO2max (conditioning), muscle size (CSA) and strength (1-RM) over 6 wks (Kikuchi. 2015).
As the data in Figure 1 reveals, significant increases in VO2max from pre- to post-test were observed only in the CT group (p=0.010, ES=1.84), but not in the RT group (p= 0.559, ES= 0.35). The rest of the results in Figure 1, however should be kind of surprising to anyone who has read the researchers conclusion that "our data indicate that concurrent lower limb sprint interval training interfere with arm muscle hypertrophy and strength" (Kikuchi. 2015).

No, you are not mistaken. The average muscle size and strength gain in the combined training group was larger. The reason the scientist still claim that their study would show that HIIT impedes strength adaptation is a statistical one. While the changes in the CT group had p-values p > 0.05 and were thus not statistically significant. The (albeit smaller) mean increase in the RT group was significant. Accordingly, the corresponding "effect size" in the RT group is larger than the one in the CT group and thus HIIT training must be bad, right? Well,... I don't think so.
If you take a closer look at the individual muscle  size and strength development, you should notice that being afraid that sprints would ruin your arm development is unwarranted and the statistical significance and effect sizes of the changes practically irrelevant.
Beware of bling faith in abstracts! If you look at my plot of the individual data the scientists luckily published with their full-text, it is yet obvious that this study does not prove and if we are honest, not even really suggest that there practically relevant negative effects of doing HIIT in this workout. If you just read the conclusion to the abstract, which reads "our data indicate that con-current lower limb sprint interval training interfere with arm muscle hypertrophy and strength" (Kiku-chi. 2015), you may be inclined to make unne-cessary changes to your workout that are neither necessary or productive. After all, the objective result of the study is that in some individuals it is possible that the addition of HIIT to an arm workout may have a minor impact on their gains.

In view of the facts that there's (a) one person with a roughly ~41% increase in sleeve sizes in each group and that (b) the average increase in sleeve size would be 23% in the CT and only 21% in the RT group if the two outlayers who lost muscle (one in each group) were excluded, though, I would suggest you ignore this possibility unless you realize that you're making no gains at all with concurrent training. This doesn't falsify the scientists' conclusion, which is based on scientific standard procedure, i.e. look for statistical significant results, use those to make your conclusion, but I felt I needed to write this article to put the theoretically correct interpretation of results of an unquestionably under-powered study into perspective | Comment!
References:
  • Kikuchi et al. "The effect of high-intensity interval cycling sprints subsequent to arm-carl exercise on muscle strength and hypertrophy in untrained men: A pilot study." Journal of Strength and Conditioning Research Publish (2015): Ahead of Print | DOI: 10.1519/JSC.0000000000001315