More Evidence in Favor of the Post!-Workout Coffee: 250mg Caffeine 2x à Day Soothe Muscle Soreness (DOMS), Sign.

Delicious, ergogenic and good for sore, damaged muscles: coffee!

You will remember that caffeine can improve skeletal muscle glycogen resynthesis after workouts. The corresponding study by Pedersen et al. is yet no longer the only study which makes the post-, not pre-workout coffee attractive for athletes and gymrats alike.

In their latest paper in the Journal of Strength and Conditioning Research, Aron R. Caldwell and colleagues report the results of an interesting experiment, an experiment with a hypothesis that was based, mainly, on the well-known, but short-lived (2-4 hours) analgesic (=pain relieving) effects of the world's favorite drug: caffeine.

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To test, whether those would help athletes to recover faster, Caldwell et al. simply postponed the usual caffeine ingestion schedule that would have the subjects ingest caffeine pills or caffeinated beverages ~1 hour before exercise, to maximize blood caffeine concentrations for ergogenic effects during exercise or testing, to the post-workout window. And since the authors also speculated that "the primary mode of action of caffeine during recovery", if there was any, was "analgesic in nature, such that any reduction in pain sis directly related to blood levels of caffeine" (Caldwell. 2017). They had their subjects ingest caffeine several occasions throughout the day - here twice a day - so that any measurable decreases in skeletal muscle soreness would be maintained. Accordingly, subjects rated muscle soreness once in the morning, before caffeine ingestion (i.e., when blood caffeine levels were low), and once midday (i.e., when blood caffeine levels were high).

The exercise stimulus the subjects, adult men (n = 25; 53 ± 10 years) and women (n = 5; 46 ± 11
years) were subjected to was nothing less than the 2015 Hotter’N Hell Hundred in Wichita Falls, TX, a 164-km bicycle ride that takes place, above all, in August. All subjects had previously completed at least one 164-km cycle ride and were not naive to caffeine consumption (habitual intake = 230 mg of caffeine per day).

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"To examine the effects of caffeine ingestion on soreness and functionality, subjects who completed a 164-km recreational cycle ride were matched for body mass, age, and sex, and were randomly assigned to ingest caffeine or identical looking placebo pills after completion of the ride. To examine the effects of caffeine or placebo ingestion on DOMS and functionality during recovery, subjects continued ingesting caffeine or placebo twice a day, once in the early morning on waking and once at noon, for the next 3 days. 

Measures of perceived function ality and soreness were obtained before and after the ride, and in the morning and in the afternoon of the 3 subsequent days before ingesting pills. Morning and afternoon measures of functionality and soreness were separated to evaluate if the caffeine dosing schedule effected subjects perception of these 2 variables" (Caldwell. 2017).

As hinted at previously, the subjects ingested the caffeine pills (3mg/kg, i.e. 252 mg on average, per serving) in the mornings 1–4 days post-ride (700 or 800 hours) and in the afternoons on 1–3 days post-ride (1200 hours) after being prompted by e-mail and text message. And yes, it would be interesting to see how they'd done if they'd got this caffeine from coffee - probably better! After all, "Coffee Beats Caffeine in the Gym!" (read more).

Figure 1: Mean (±SD) overall ratings of perceived muscle soreness (RPMSOVERALL) when assessed in the (A) morning and (B) afternoon, and RPMS specifically in the legs (RPMSLEGS) in the (C) morning and (D) afternoon. *Significant difference p < 0.05 between conditions, #Trend toward significance p = 0.10 between conditions (Caldwell. 2017).

The scientists' analysis of their subjects ratings of perceived muscle soreness (RPMS) and perceived lower extremity functionality (LEF) revealed that...

• the caffeine group tended to have lower overall RPMS in the afternoon versus placebo (i.e., main effect of group; 1.1 ± 0.2 vs. 0.5 ± 0.2; p = 0.09). 
• the caffeine group had significantly lower afternoon RPMS for the legs (main effect of caffeine; 1.3 ± 0.2 vs. 0.5 ± 0.3; p = 0.05), and
• there was no measurable difference in terms of perceived lower extremity functionality

Overall, these results provide additional evidence that caffeine does not have to be consumed exclusively pre-workout to have a measurable benefit in athletes and gymrats. What remains to be seen, though, is whether the perceived reduction in muscle soreness goes hand in hand with objectively measurable increases in exercise performance and/or markers of recovery in the days after an intense sporting event like the 2015 Hotter’N Hell Hundred.

Here it is: Scientific evidence caffeine is the among the healthiest addictions known to man: "The Coffee³ Advantage Equation: 3 x 250mL Coffee / Day + 2x4 Weeks ➫ -1kg Body Fat, Satiety ⇈ (Ghrelin ↘ + 5HT ↗) + Cancer Protective 16% Reduction in DNA Breaks = Health³" |  more

Preliminary, but intriguing: With this being only the second study that provides decently convincing evidence that your caffeine addiction could significantly promote crucial aspects of your exercise recovery (reduced muscle soreness in this and increased glycogen resynthesis in the previously cited study by Pedersen et al.), it would be premature for trainers to prescribe a daily dose of two large bowls of coffee to all their athletes (from a mere health perspective this may yet make sense as you've learned in dozens of articles about coffee's health effects here at the SuppVersity). A guilty conscience, on the other hand, should be a thing of the past for all of you who cannot stay away from their beloved coffee after workouts... just make sure that you don't reach a daily caffeine intake that stresses at which the stimulating effects backfire (for many that's > 800mg) | Comment on Facebook!

References:

• Caldwell, Aaron R., et al. "Effect of Caffeine on Perceived Soreness and Functionality following an Endurance Cycling Event." The Journal of Strength & Conditioning Research (2017).
• Pedersen, David J., et al. "High rates of muscle glycogen resynthesis after exhaustive exercise when carbohydrate is coingested with caffeine." Journal of Applied Physiology 105.1 (2008): 7-13.

Ingestion of 400mg Caffeine Before a Workout Can Prevent Delayed Onset Muscle Soreness in Resistance Trained Men

Too many side-laterals without coffee?

Still having DOMS despite Alex Leaf's article on "DOMS - Delayed Onset Muscle Soreness: What Is DOMS & How Can It Be Managed? Science, Strategies, Supplements" (read more)?

In that case you are probably not a great fan of pre-workout products, coffee or energy drinks, because if you were, it is not unlikely that you had - instinctively, if you will - done everything right by consuming a hefty dose of the world's #1 OTC drug, caffeine, before each of your workouts.

400mg is plenty, but it does the trick

In case you have no clue what I am talking about, I'd suggest you take a look at the results of a recent paper by Hurley, Hatfield, and Riebe in the Journal of Strength and Conditioning Research (Hurley. 2013). In a series of tests that involved a strenuous biceps workout 4 sets of 10 bicep curls on a preacher bench, followed by a fifth set in which subjects completed as many repetitions as possible. The workout that was performed twice, with a one-week "wash-out" period - once with and once without the ingestion of 5mg/kg of caffeine 1h before the training session.

When the scientists compared the performance, perceived exertion and post-workout muscle soreness parameters they found that the ingestion of 5mg/kg caffeine ...

• had a beneficial effects on the perception of muscle soreness, 
• reduced the levels of perceived exertion, and
• lead to significant increases in performance

As you can see in Figure 1 the equivalent of ~2-3 cups of coffee did nut just ameliorate the pain on day 2 after the workout (that's usually when DOMS hits you hard). It did also speed up the "regeneration", or rather the reduction of pain.

Figure 1: Soreness values expressed relative to baseline testing (left) CK levels after the training session and number of repetitions on the all-out set (right; Hurley. 2013)

I have to admit, I was tempted to write that caffeine sped up the recovery process, but if you read part II of Alex' two-part series on DOMS, you will be aware that it is not warranted to use DOMS as a marker of regeneration ("DOMS - Delayed Onset Muscle Soreness: No Pain, No Gain? Is DOMS Necessary to Build Muscle?" | learn more).

The repeated bout effect is the opposite of the anabolic resistance that can occur after weeks of training | learn more

What about the repeated bout effect? What if it skewed the results? The increase in performance and reduce in muscle damage upon the exposure to a "conditioned" stimulus could in fact have led to lower DOMS values in the second of the two testing session. Hurley et al. do however point out that this effect would be minized by counterbalancing and appropriate randomization as it was conducted in the study at hand.

The non-existent effects on the creatine kinase (CK) levels of the the 12 healthy resistance-trained men (age 18–25 years) supports Alex' assessment that the link between CK and DOMS is a temporary one: While the peak values of DOMS and CK occur at the same time, a high CK level does neither predict a high degree of delayed onset muscle soreness, nor vice versa.

So what's the mechanism here

In view of the fact that the continuous provision of caffeine throughout the recovery phase did not lead to similar / increased reduction in DOMS, it appears certain that the effects of caffeine are acute. This means it works only, if it is ingested 1h before the workout and will thus achieve it's peak value when you are actually working out (depending on the dosage and delivery method, the caffeine levels peak after 40-60 min).

As Hurley et al. point out, the effect could be brought about by a partial blockade of the natural increase in muscular adenosine concentrations that have been observed to increase in the working muscle and blood after high-intensity exercise in previous studies (Tarnopolsky, 2000; Davis. 2003; Motl. 2006). It would also stand in line with the (unsurprising) observation that the subjects’ perceived exertion was significantly lower with caffeine in the final 3 sets of exercise - an effect that has also been attributed to the adenosine-inhibiting effects of caffeine (Davis. 2003):

"This response is attributed to the role of caffeine as a CNS stimulant and inhibiting adenosine receptor activity. Caffeine stimulates the CNS by secreting serotonin into the cerebral cortex, which results in mood improvements, increased mental awareness, and decreased fatigue and tiredness. This is all a result of inhibited adenosine activity thus reducing perception of pain, which could increase ability to perform more repetitions." (Hurley. 2013)

In view of the fact that the adenosine levels have not been accessed, the authors are eventually still stuck for an answer with respect to the exact underlying mechanism of the anti-DOMS effects of caffeine. Adenosine is a likely candidate, though, and before I would do a follow up study on this, I would rather take some money to find out whether 400mg of caffeine taken before a PM workout won't be doing more harm than good by having profound negative effect on your sleep quality.

Sometimes the things we learn from scientific studies have questionable, limited or no practical relevance. For others, like the study at hand or a previous study on the "muscle shaping effects" of certain exercises, this is luckily not the case (read more)

"Who cares about mechanisms, if it works?" I guess in view of the many in-vitro studies we are being bombarded with on a daily basis, most of you will probably agree that not knowing the exact mechanism of the DOMS-reducing effects of 5mg/kg of coffee is less problematic than knowing about the mechanism by which a certain substance works, but being clueless whether and at which doses it will produce the desired effects in humans - right?

Right! Unfortunately, even the results of the study at hand come with a small "*" [asterisk] to indicate that the benefits were observed in subjects who consumed coffee and caffeinated beverages only occasionally. Based on the observation that the performance enhancing effects of caffeine do not differ between habitual / non.habitual caffeine consumers (Tarnopolsky. 2000; Astorino. 2007), it does however appear likely that this is not going to be an issue.

References:

• Astorino TA, Rohmann RL, Firth K, Kelly S. Caffeine-induced changes in cardiovascular function during resistance training. Int J Sport Nutr Exerc Metab. 2007 Oct;17(5):468-77.
• Davis JM, Zhao Z, Stock HS, Mehl KA, Buggy J, Hand GA. Central nervous system effects of caffeine and adenosine on fatigue. Am J Physiol Regul Integr Comp Physiol. 2003 Feb;284(2):R399-404. Epub 2002 Oct 24.
• Hurley CF, Hatfield DL, Riebe DA. The effect of caffeine ingestion on delayed onset muscle soreness. J Strength Cond Res. 2013 Nov;27(11):3101-9.
• Motl RW, O'connor PJ, Tubandt L, Puetz T, Ely MR. Effect of caffeine on leg muscle pain during cycling exercise among females. Med Sci Sports Exerc. 2006 Mar;38(3):598-604.
• Tarnopolsky M, Cupido C. Caffeine potentiates low frequency skeletal muscle force in habitual and nonhabitual caffeine consumers. J Appl Physiol (1985). 2000 Nov;89(5):1719-24.