Dorian Varović

Our systematic review and meta-analysis exploring the effects of caffeinated chewing gum on muscle strength, endurance and jump performance has just been accepted for publication in @JSCRonline Cheers to @Jozo_Grgic for a great collab! Key findings and practical takeaways:

@BradSchoenfeld Thanks for sharing, Brad! And agree! :)

There is strong evidence that similar hypertrophy can be achieved across a wide range of loading schemes (~5 to 30+ repetitions), provided sets are performed close to muscular failure. That said, some data suggest fiber type–specific differences, with heavier loads potentially favoring Type II fiber growth and lighter loads favoring Type I fibers. A recent meta-analysis offers preliminary support for this idea, although the limited number of eligible studies warrants cautious interpretation. From a practical standpoint, those aiming to maximize hypertrophy may benefit from incorporating both heavy and light loads within a training program. For the general population, however, loading range is unlikely to have a meaningful impact on overall muscle growth—so selecting loads based on preference and adherence is a sensible approach. sportrxiv.org/index.php/serv…

Our new systematic review and meta-regression exploring the relationship between training load and muscle fiber hypertrophy has just been pre-printed. Kudos to @StianLa07849895 and @Jozo_Grgic for awesome collaboration! You can read the paper here: sportrxiv.org/index.php/serv…

@SamaHoole @BradSchoenfeld @BradSchoenfeld is right, the current evidence does not support some of the recent claims Chris has been putting out. As for the Haun et al. study you've linked. Well..you're in luck. I hope this at least gives you something to think about: instagram.com/p/DOtKAjriNfU/…

I appreciate the shout-out, but you need to have a washout period for edema in order to accurately look at the hypertrophy of low vs high reps. And my argument is backed by studies like this that show that high volumes do nothing for hypertrophy if they aren't taken near failure. frontiersin.org/journals/nutri…

When you train in the 10-12 rep range, most of your reps have no effect on growth. When you train in the 4-6 range, virtually all of your reps are growth reps. It's simply the most efficient way to build muscle.

@BradSchoenfeld Thanks, Brad! To add on, while some have argued that isometric training is inferior to traditional RT, our data do not support such claims (as do a few other studies on the topic). But, still a lot more work to be done on the topic in the future!

New from our group: The first study to investigate hypertrophy in isometric actions vs dynamic actions in an ecologically valid manner in trained lifters. When performed at long muscle lengths, isometric had similar (or better) effects on quad growth💪 cdnsciencepub.com/doi/10.1139/ap…

We're recruiting participants for our study exploring the effects of isometrics at long muscle lengths vs. full range of motion on hypertrophy. If you're in or near Zagreb and would like to participate or know someone who, shoot me a DM or apply here tinyurl.com/IsometricsStudy

@BradSchoenfeld @JamesSteeleII @MiloWolf12 @Jozo_Grgic Finally, if positive effects of training at longer muscle lengths on regional muscle hypertrophy exist, they may be the greatest at the distal sites. However, due to the imprecision in the posterior distributions for effects, our findings should be considered exploratory.

Our meta on the effects of muscle length on regional muscle hypertrophy was just pre-printed. Happy to see this finally out and we welcome any feedback pre-review! sportrxiv.org/index.php/serv… @BradSchoenfeld @JamesSteeleII @MiloWolf12 @Jozo_Grgic and my supervisor, Pavle Mikulic.

@BradSchoenfeld @JamesSteeleII @MiloWolf12 @Jozo_Grgic As of writing this, only 12 studies were conducted on the topic which leaves a ton of work to be done, and we hope that our suggestions for future research on the topic will be helpful for generating ideas.

@BradSchoenfeld @JamesSteeleII @MiloWolf12 @Jozo_Grgic Important to note that effect sizes presented in the paper reflect the estimated impact of a mean muscle length difference of ~50% (i.e., the difference between 25% and 75%).

@BradSchoenfeld @JamesSteeleII @MiloWolf12 @Jozo_Grgic A unique approach we took was presenting several models with different priors as @JamesSteeleII held far more skeptical belief's about potential effects of different muscle lengths. This will allow readers to interpret the findings based on...well, their own priors ;)

@BradSchoenfeld @JamesSteeleII @MiloWolf12 @Jozo_Grgic For our pre-registered model estimates of effects were slightly greater at distal sites (SMD: 0.2), probability of finding a meaningful positive effect and the pooled effects were smaller (50.70-69.78%; SMD: 0.10-0.15) for both mid-belly and proximal sites

I've been invited on the School of Muscle podcast to discuss our findings from a recent MA on the effects of caffeine on jumping performance in females. Tried to give some cool practical takeaways pertaining to RT as well. :) youtu.be/CRPD53OOQ74

@Jozo_Grgic 3/3 An ergogenic effect of caffeine was consistently found in analyses for testing time of day (morning, evening, mixed morning or evening, or not specified), caffeine dose (≤3 mg/kg or >3 mg/kg) and test type (squat or countermovement jump).

Our systematic review and meta-analyis on moderators of caffeine's effects on jumping performance in females was officialy published in the Journal of the American Nutrition Association Kudos to @Jozo_Grgic for awesome collab once again! :) tandfonline.com/doi/full/10.10…

@Jozo_Grgic 2/3 In a subgroup analysis for phase of the menstrual cycle, the ergogenic effects of caffeine on jumping performance were the largest in the follicular phase, possibly due to caffeine attenuating the drop in volintary activation.

@Jozo_Grgic 1/3 We found a small but very precise ergogenic effect of caffeine on vertical jumping performance in females. Similar effect sizes to the ones found in other types of activities examining caffeine's effects.

@JimAshmoreUS @BradSchoenfeld SB has several absorption mechanisms. One pertaining to the stomach is that part of the ingested SB will be removed via CO2.Alkalization of gastric juice will also likely stimulate basolateral Cl-/HCO3- antiporter which is mediated by H+/K+ATPase that can regulate HCO3- transport

@BradSchoenfeld @DorianVarovic Wouldn’t stomach acid buffer the ingestion of sodium bicarbonate? Seems dubious to me.

Our new study suggests a potential benefit of sodium bicarbonate on number of reps during multiset submax RT. Effect is small and of questionable meaningfulness for gen pop; perhaps benefit for certain athletes? Kudos to @DorianVarovic for leading the way journals.lww.com/nsca-jscr/page…

@bradympowers @BradSchoenfeld Incidence of side effects was actually smaller than expected if I may say so for most of the participants. Employing strategies such as dividing the dose in several smaller ones, eating CHO meal beforehand or the use of enteric coated capsules might help with GI distress.

@BradSchoenfeld @DorianVarovic Shitting my brains out isn’t worth an extra rep.