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Supplement Review: Beta-Alanine for Athletic Performance

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Question. Why are supplements always a topic of conversation? What makes them so relevant, All. The. Time?

Well, we have to consider the competitiveness of sports nowadays. Developments in sports science have revealed new strategies to outrun, overpower, and dominate opponents. These developments have made sports MORE competitive, and in cases like Soccer, each game sees more passes, more tackles, and further distances covered. Consequently, this simply means the athletes need to be better, faster, and (yes) stronger.

This is why supplement marketing is so powerful and influential. AND why their advertisements, promising advantage and improved performance, are gobbled up without careful thought by athletes or their coaches. Unfortunately, this means supplements can be an athlete’s primary ergogenic strategy over more important ones, like food.

That’s why supplements are, and always will be, discussed. There’s a demand. I just hope we don’t lose sight of that demand, and maybe understand whether your demand for supplements is warranted. Because, while some supplements can be universally useful to athletes, others have a narrow target audience. In other words, some supplements have a very narrow influence on physiology and are only useful in very specific circumstances. With that, I’ll introduce this month’s supplement: Beta-Alanine.


Introduction – The What’s and How’s of Beta-Alanine

What makes beta-alanine a useful supplement to athletes? Well, it’s the rate-limiting ingredient (science words for “most needed”) to create carnosine, AKA “beta-alanyl-L-histidine”. Basically, your muscles have enough L-histidine, but not enough beta-alanine, to produce carnosine. This means your muscle carnosine levels are dependent on the amount of beta-alanine you make available. And while your liver is capable of creating beta-alanine as a byproduct, it’s still insufficient to change carnosine levels. Therefore, your muscle carnosine levels appear to be dependent on your dietary beta-alanine consumption.

Why worry about your muscle carnosine, though. Carnosine might be new to you, but it does play an important role as an intramuscular buffer. Essentially, carnosine accepts protons, or hydrogen ions (H+), that accumulate during high-intensity muscle contractions. Typically, the accumulation of H+ would create an acidic environment within the muscle and disrupt the functionality, causing muscle fatigue. Carnosine, as a buffer, is able to mitigate the rise in acidity by accepting H+ from the muscle cell, helping to neutralize the acidic effect and maintain normal functioning. Therefore, the carnosine system is an essential process for athletes relying on H+-generating systems, such as anaerobic glycolysis, to prevent early fatigue in their event.

By limiting H+ accumulation, the athlete’s muscle becomes more fatigue resistant. Typically, an acidic environment limits muscular function in several ways, including:

1.     Reduce the force- and power-producing capacity of the muscle.

2.     Interfere with metabolic enzymes needed to generate energy. Enzymes like phosphofructokinase (PFK) are slowed in acidic environments, meaning fast-energy systems, like anaerobic glycolysis, are slowed down.

3.     Impede Calcium release needed to stimulate your muscles to contract.

4.     Increase perception of fatigue. You basically feel like you’re working harder than you are.

Thus, carnosine’s buffering helps prevent the breakdown of these mechanics, allowing the muscle to continue working.

Where do we find beta-alanine? Carnosine exists in meat, poultry, and fish; however, carnosine is not simply taken up into your muscles after ingestion. Two carnosinase enzymes, that exist in your blood and some tissues (excluding muscle), degrade carnosine into beta-alanine and L-histidine. For this reason, ingestion of carnosine itself does not significantly raise muscle carnosine levels. This explains why beta-alanine supplementation is necessary to stimulate a significant change in carnosine levels.

In this review, we’ll examine how beta-alanine accomplishes this, what performances are improved, who should consider supplementation, and the recommended protocol to see benefits.


Claims – Why is Beta-Alanine Supplementation Note-Worthy?

As a supplement, beta-alanine’s ergogenic benefits rely on its ability to increase carnosine levels. In fact, beta-alanine supplementation does increase muscle carnosine concentrations. Research into beta-alanine supplementation shows the carnosine increases in a dose-dependent manner. This means that the more beta-alanine consumed, the more muscle carnosine levels will increase. Thus, the question becomes how this change could improve sports performance.

Essentially, by increasing carnosine levels, beta-alanine supplementation can increase the buffering capacity of the muscle AND enhance carnosine’s inherent stimulus on muscular function. This should help improve the muscle’s resistance to fatigue induced by high H+ accumulation

Based on the physiological role of carnosine, the most benefitted activities are likely those that elicit high levels of acidemia (or lactate) in the muscle. The degree of athletic improvement depends on whether (1) the increase in buffering capacity actually elicits a practical effect, and (2) that the performance event induces an environment that would benefit from improved buffering. Carnosine is also suspected to improve performance by enhancing muscular function within a fatigued muscle by improving the sensitivity of internal receptors responsible for muscular contraction.

To understand the performance effects, we’ll first review how carnosine specifically relates to improving fatigue resistance. We’ll review carnosine’s role in:

1.     Buffering

2.     Calcium sensitivity

Carnosine’s Buffering Effect

Carnosine’s normal contribution to the muscle’s total buffering capacity is relatively low. Without beta-alanine supplementation, normal carnosine levels only contribute about 6-7% of total muscle buffering. Thus, it initially appears muscle carnosine’s relative importance is too low to offer an impact on performance. However, since carnosine’s concentration can increase between 16-80%, depending on dosing factors, we could expect its buffering contribution to increase and improve capacity. In fact, performance tests analyzing buffer-related activities and tests, like time-to-exhaustion (TTE), indicate that supplementation does improve outcomes.

Carnosine’s Role in Calcium Sensitivity

Carnosine is also known to enhance the muscle’s sensitivity to calcium by regulating calcium-related enzymes and the sarcoplasmic reticulum (SR). Typically, calcium is released from the SR to allow the muscle to contract. When enzymes or receptors become desensitized to calcium, by acidity or other fatiguing factors, there is a reduction in how much force the muscle can generate. Therefore, by improving the mechanics of calcium in the muscle, carnosine can help mediate the effects of fatigue. With increased carnosine levels, through supplementation, we should expect the muscle to be able to maintain force and power output for longer.

Performance Claims

With these roles in mind, let’s investigate the types of performances beta-alanine should benefit from. That way, you can better decide if beta-alanine is relevant to your type of training and/or sport.

As we know, carnosine should help improve lactate-inducing exercises. Therefore, we would expect performance enhancements for athletes that rely on the anaerobic glycolytic system in their sport. In fact, a significant correlation was found between carnosine concentration and mean power (relative to body weight) in the final 10 seconds of the Wingate Test.

Note – The Wingate Test is 30 second, all-out cycling test that measures anaerobic power, and relies heavily on creatine phosphate and anaerobic glycolysis for energy. You can use the Wingate Test to examine peak power, mean power, and fatigue index. Mean power and the fatigue index can indicate resistance to fatigue based on how much an athlete’s power drops throughout the test.

This indicates that carnosine levels were related to improved maintenance of the athlete’s power output, during the time period we would expect to see fatigue-related performance declinations. Therefore, beta-alanine supplementation, via its effect on carnosine, helped improve this form of fatigue resistance.

Post-Supplement, athletes are able to work at a higher intensity (e.g. run at a faster pace) before lactate starts building up. This improves performance because the athlete is not limited by lactate buildup.

Studies appear to corroborate beta-alanine’s effect on fatigue-resistance. By utilizing protocols that focused on TTE, repeated effort/sprint designs, and time trials, researchers were able to conclude that beta-alanine delayed the onset of blood lactate accumulation (OBLA). This just means the muscle was able to work harder (relative to maximal effort) before lactate started to accumulate to a point that led to fatigue. In essence, beta-alanine supplementation allowed athletes to work at a higher percentage of their VO2 max before the muscle’s buffering systems could not keep up with the production of lactate and protons.

What does this mean practically? Imagine this, an athlete’s VO2 max is ~10 mph. They choose to race at ~7mph because it’s below or at their OBLA (let’s hypothetically set at 7.5 mph). This allows them to continue their pace without succumbing to fatigue and slowing down. With beta-alanine supplementation, however, OBLA would be pushed to a higher % of VO2 max. This would push OBLA from 75% of VO2 max (hence 7.5 mph) to maybe 80% of VO2 max (or at 8mph). This obvious change is why beta-alanine can potentially improve athletic performance, as athletes are able to increase performance parameters, like their race pace, without undergoing extra training.

In fact, studies show beta-alanine supplementation increases supramaximal TTE, AKA how long you can last at VO2 max over 100%. This shows an improvement in fatigue resistance at supramaximal intensities. It’s important to note, however, that beta-alanine supplementation has a fairly narrow ergogenic effect. Meta-analyses indicate beta-alanine’s effectiveness is based on the duration of the high-intensity performance, particularly for events lasting 1 to 4 minutes. Durations <1 minute likely don’t see improvements because acidosis is not a limiting factor in those events; instead, issues like creatine phosphate storage, form, or skill may be the primary limiters. Additionally, events >4 minutes may see some improvements, but not to the same degree. However, long-duration events, like road cycling or long-distance running, could see benefits in performance, but only in their final sprint at the end of the event.

In addition to event duration, event characteristics can also influence the effectiveness of beta-alanine supplementation. Repeated effort protocols, such as the Yo-Yo Intermittent Test, Loughborough Intermittent Shuttle Test, and Repeated Sprint tests, help us understand the influence of work-to-rest ratios on beta-alanine effectiveness. For example, while the Yo-Yo test was improved by beta-alanine supplementation, the Loughborough test was not. It’s believed that the long rest period in the Loughborough test would reduce the acid buildup in the muscle, thus reducing the effects of fatigue. This further affirms the narrow specificity of carnosine in improving performance.

Finally, beta-alanine supplementation also appears to delay neuromuscular fatigue, as indicated by tests utilizing Physical Working Capacity at Fatigue Threshold (PWCFT). You’re probably wondering… “What?” During normal neuromuscular fatigue, your nervous system has to electrically excite your muscle more frequently in order to maintain power output. Essentially, your nervous system increases electrical activity to recruit more muscles because other fibers have fatigued and can’t keep up with the demand. Therefore, since beta-alanine delays the need for heightened stimulation, either through buffering or calcium sensitivity, your muscle is capable of resisting not just mechanical fatigue but also neuromuscular fatigue.

Fatigue resistance should also improve training quality. This allows athletes to train at higher intensities and volumes, which should elicit greater gains through more significant adaptations. Remember, though, that this is specific to anaerobic glycolytic activities. Therefore, we would not expect improvements in strength, as confirmed by studies, because strength-specific training tends to not be limited by lactate-related fatigue. 

To conclude beta-alanine’s performance claims, let’s summarize known improvements:

1.     Delayed OBLA

This will allow athletes to maintain their performance at a higher relative intensity, or last longer at supramaximal intensities. Additionally, delayed OBLA will improve the sprint performance of aerobic athletes at the end of their event by limiting lactate build up.

2.     Improved Neuromuscular Fatigue

By delaying neuromuscular fatigue, athletes are able to tap into “unused” muscle fibers later in their event, thus improving their ability to maintain their power output.

This helps make it obvious that beta-alanine supplementation focuses on resisting fatigue. But, where are its effects greatest? Remember, exercises or events lasting 1-4 minutes will see the most improvement with beta-alanine supplementation, particularly when completed at supramaximal intensity (>100% VO2 max). Additionally, intermittent performances, typical of repeated sprints or field sports, only see improvements based on the protocol (AKA work-to-rest ratio). This means, beta-alanine’s usefulness may be very specific to a certain subset of athletes and will not be universal to ALL ATHLETES. Instead, beta-alanine use should be dictated by the individual.


Use – What Beta-Alanine should you use and How?

Now, you might be interested in trying out beta-alanine. You’ve determined that your performance goals can be enhanced by a beta-alanine protocol; but what exactly are you looking for?

Products

Well, first, what product are you looking for? We know consuming carnosine itself isn’t going to have the same effect since our blood carnosinase will simply degrade it before entering the muscle. However, simply looking for beta-alanine won’t cut it. Recently, legal authorities have actually intervened in beta-alanine supplement matters because of a patent by Natural Alternatives International (NAI).

Skipping over the legal issues, you’re essentially looking for NAI’s patented CarnoSyn®. Products without this patented version likely come from foreign labs, regulated by different policies, and may be alright as long as they’re third-party tested. The patented beta-alanine product, CarnoSyn® comes in 2 forms: Instant-release (IR) or Sustained-release (SR). Additionally, these products can come as powders, capsules, tablets, chewables, or stick packets. The 2 NSF-Certified products, Thorne® and Klean Athlete, provide SR-CarnoSyn® in tablet format.

Note – For athletes regulated by anti-doping laws, like the NCAA or IOC, it’s necessary to choose products that are NSF-Certified for Sport or third-party tested. This means that an outside lab has verified ALL the ingredients in the product and found no additives not indicated on the label. This is important, as supplements are not strongly regulated and non-third-party tested products may have illegal substances that fail your next doping test.  

            Below are some beta-alanine products that offer CarnoSyn®, including both NSF-certified and non-third-party tested products currently available (this is a short list compared to what actually exists). For athletes not restricted by anti-doping laws, be aware that NSF-certified products can be more expensive, so it’s up to you to weigh the pros and cons between price and purity. 

Dosage

Beta-alanine dosing is a little more complex. Research protocols provided doses between 1.6-6.4 g/d for 4-28 days, which increased carnosine by 16-80%. Therefore, it is absolutely reasonable for athletes to follow similar protocols. However, carnosine levels were found to be related to the total beta-alanine consumed over a given time period. Therefore, if an athlete is supplementing beta-alanine for a specific competition on a specific day, the goal should be to maximize the total beta-alanine consumed up to that point. They can achieve this by consuming 4-6.4 g of beta-alanine per day.

To me, however, the original 1.6-6.4 g/d range is too broad. Instead, I find the prescription of 64 mg/kg/day (and up to 80 mg/kg/day) is more useful to an individual. Then simply double-check your mg/kg prescription to 4-6.4 g/d to ensure you’re in the right range. One caveat, however, is for anyone using IR CarnoSyn®. Due to its side-effect, paresthesia, individuals supplementing with IR CarnoSyn® should limit their individual doses to <10 mg/kg. SR CarnoSyn® users, however, should be able to consume up to 1.6 g/dose before experiencing paresthesia.

This amount of dosing can be a significant commitment to an athlete, unfortunately. Once you realize that IR- and SR-forms can take up to 10 to 4 doses, respectively, it becomes clear that maintaining this regimen can become burdensome. Therefore, once athletes have optimized their carnosine levels, they should take advantage of maintenance doses. A maintenance dose of just 1.2 g/d, which is easily consumed in 1-3 doses (depending on your beta-alanine form), can maintain 30-50% of carnosine above baseline. Therefore, athletes can consider periods to (1) optimize carnosine levels and (2) maintain carnosine depending on their competitive schedule.

Note – Did you know that many pre-workout supplements have beta-alanine in them. This explains why many people experience an itching/tingling sensation 30-60 minutes into their workout. That means athletes need to account for how much beta-alanine is in their pre-workout supplements before determining their beta-alanine dosage.

Timing

Beta-alanine supplementation is less time-sensitive than other supplements. SR forms are just as effective as IR in increasing carnosine. However, since IR CarnoSyn® requires more dosages, the time intervals between dosages will be shorter. For instance, 10 doses would be needed to maximize the daily IR CarnoSyn® dose and minimize paresthesia, meaning athletes may be supplementing as frequently as every 1-2 hours. SR CarnoSyn®, on the other hand, can achieve a high daily dose, of 6.4 g/d, with just 4 doses throughout the day. This would correspond very well with 4 protein-rich meals distributed throughout the day.

Another caveat is that IR beta-alanine is also better absorbed with a meal containing carbohydrates and protein. Unfortunately, I doubt many athletes are consuming up to 10 meals in a day to correspond with this requirement, meaning some beta-alanine doses lose their effectiveness. Together, this points to the SR CarnoSyn® product offering more advantageous dosing protocols than the IR form.

Finally, how long will it take for carnosine levels to increase? The research indicates that carnosine can increase in just 2 weeks, with the average protocol for raising carnosine being 4 weeks. A longer protocol, up to 18 weeks, is needed to maximize carnosine levels to their peak concentration. However, this requires the upper-end of the dosing spectrum, seeing as carnosine concentration is related to the total beta-alanine consumed over a given time period. Further increases in carnosine, however, would be difficult without significant side-effects, namely paresthesia.

Washout

The washout rate, or the loss of muscle carnosine concentration, can actually be useful to athletes and their coaches. Carnosine degrades relatively slow once beta-alanine supplementation is ceased. This slow degradation is likely due to the lack of muscle carnosinase (but that’s not confirmed). With a slow washout, athletes can expect their carnosine levels to remain 70-80% elevated after 3 weeks, and return to baseline after 9 weeks. Therefore, the slow washout, and easy maintenance dose, allows for beta-alanine supplementation to remain useful long-term as it’s easy to keep beta-alanine elevated.

Like most supplements, there is intervariability (differences between people) in the accumulation and washout rate. Therefore, every athlete should gauge their response to supplementation to determine if the strategy was actually effective.

Side Effects

Beta-alanine supplementation (particularly IR-CarnoSyn®) can cause paresthesia. This is an abnormal sensation of tingling, itching, or burning of the skin, and has been related to high concentrations of blood beta-alanine due to rapid absorption from the intestines. Fortunately, paresthesia is not permanent nor harmful; however, if beta-alanine is consumed consistently throughout the day, as is the case for IR-CarnoSyn®, then athletes may expect to experience paresthesia fairly constantly.

Due to these side-effects, it’s necessary to limit doses to 10mg/kg of IR beta-alanine. If this makes achieving sufficient total beta-alanine needs difficult, athletes should consider using SR forms (up to 1.6g per dose) to eliminate chances of side-effects.

Special Considerations

Supplementing with beta-alanine comes with a few special considerations and caveats. These should be considered by any athlete thinking about using beta-alanine to improve performance as they might influence the effectiveness. For instance, similar to other supplements, beta-alanine supplementation appears to have considerable interindividual variability, meaning everyone might have a different response to supplementation or the Ol’ Responder versus Non-Responder scenario. Your teammate might experience a significant change in performance, improving their Yo-Yo Test, while you don’t notice much of a difference. The reason for this variability isn’t well understood but is thought to be due to differences in absorption in the intestines, uptake by the muscles, or resting carnosine levels. This means athletes should monitor how effective supplementing beta-alanine is to determine if it’s worth continuing.

Another caveat relates to the specificity of beta-alanine’s action. As noted earlier, endurance athlete’s specific energy systems don’t rely too much on carnosine’s mechanics to fuel endurance activities. This is particularly true during competitive races when endurance athletes aren’t working at supramaximal intensities. However, as the research indicates, supplementation does improve supramaximal exercise, which can still be useful to endurance athletes. How? Essentially, supplementation can improve the quality of training, allowing the athlete to improve their lactate threshold and OBLA. These improvements should enhance their endurance capacity. Therefore, while supplementation won’t improve the actual endurance race, it can improve the training to develop the pace used in the event. Additionally, carnosine’s slow washout allows for athletes to cease supplementation, reducing the burden, while still benefiting from lasting carnosine levels.

Finally, the use of beta-alanine in conjunction with other supplements has also been studied. The belief is that a combination of supplements may provide an additive effect compared to each alone. The downside, however, is the cost of including more supplements in an athlete’s regimen. Athletes should question whether additional supplements improve performance enough for their cost. There are 2 supplements currently studied with beta-alanine: Creatine and Bicarbonate.

The combination of creatine with beta-alanine was shown to improve fatigue rates, training volume, and body composition in American Football players. Additionally, these improvements were greater than creatine alone. Unfortunately, the researchers did not use a beta-alanine only group, so it’s difficult to understand the true effect of beta-alanine. It’s believed that beta-alanine helped elicit this difference because it improved training quality, allowing subjects to amass enhanced adaptations and results.

Bicarbonate is similar to beta-alanine because it targets a physiological buffering system. While carnosine buffers the intracellular environment, within the muscle cell, bicarbonate buffers the acidity in the blood, outside of the cell. Thus, using these in combination was thought to improve the buffering capacity of the whole body. The question becomes whether a single buffer, bicarbonate or carnosine, is sufficient by itself or if buffering is even the limiting factor at this point. Studies appear to indicate an additive effect in a 4-min cycling time trial and 100m and 200m swimming times, but not significantly. This simply means it appears there were improvements, as athletes were able to recognize benefits, but the results weren’t better enough to say for sure. Significant results were only seen in intermittent supramaximal bouts, likely due to the higher acidosis response. Therefore, bicarbonate may not provide a significant improvement in performance, but the individual response could sway either way. The athlete should consider the pros and cons of trying the combination and analyze whether any improvements are worth the use


 Practical Application – What Sports would Benefit?

Hopefully, beta-alanine makes a little more sense to you now. But it still might not. The issue with supplements is many of them target very specific athletes because of their very specific adaptation. For this reason, it’s nice to lay out beta-alanine’s magic.

1.     Carnosine increases are dose-dependent, meaning the total amount of beta-alanine consumed dictates carnosine concentration. Typically, using a high-end supplementation protocol (~6 g/d) can increase carnosine by ~60% within 4 weeks, which is enough to start seeing performance improvements. Therefore, athletes should be cognizant of this time period to begin analyzing whether it’s worth continuing supplementation. By 18 weeks, carnosine levels, and their effects are maximized.

2. Results indicate that trained athletes see small benefits. BUT, and it’s a big but, these benefits are still quite significant in the real-world setting. For instance, an improvement of just under 3% on the world stage would improve a 1500m race by ~6 seconds, enough to move a last-place finalist into the Bronze medal.

3.     Beta-alanine targets very specific physiology, meaning the performances it improves is also very specific. These benefits it:

a. High-intensity exercise and incremental tests between 1-4 minutes are improved by delayed ventilatory threshold, OBLA, and neuromuscular fatigue,

b.     Enhanced gains in lean body mass related to improved training, and

c.     Improved continuous efforts at supramaximal intensities as indicated by VO2 peak and TTE test, related to improved training AND buffering capacity.

All of this means the use of beta-alanine should be decided on an individual basis. Team sports coaches should not simply advise all of their athletes to supplement beta-alanine, especially because the protocol can be quite burdensome. If the choice to supplement has been decided, athletes should monitor their performance to determine whether beta-alanine is improving their performance to be worth the cost and burden.

Of the athletes that might benefit from beta-alanine, many are related to high-intensity and supramaximal activities. This includes: Cycling, rowing, swimming, combat sports, and some field sports. Check out the table below for an easy overview of who might find beta-alanine Useful, Potentially Useful, or Not Useful

If you’re training for any of these “Useful” sports, you could consider supplementing with beta-alanine. It might help improve your time trials or train harder in the gym. Just remember to track your progress so you can determine if supplementation was as useful as you expected. Many of the “Potentially Useful” sports could see performance improvements because beta-alanine could improve the quality of training related to these sports. So, while you may see improvements in the gym, just be sure to check how your time trials or fieldwork compare. If you can’t translate changes in the gym to your real-life practice, beta-alanine probably isn’t worth it. If you’re in the last group, “Not Useful”, then beta-alanine just doesn’t target your performance-specific physiology. YAY. You don’t need to worry about paying MORE to be better. Don’t worry though, there’re plenty of options for you to consider, and by striking this one off your list your choices just got easier.


Conclusion

After each of these reviews, it’s important to highlight the intention of this article was to provide a complete overview of beta-alanine for athletes to use in their decision-making process. No supplement should just be started on a whim; that’s why we should:

(1)   Understand the function and claims – Determine whether the supplement is relevant to an athlete’s sport. If a supplement doesn’t target physiology related to an athlete’s performance then there’s no need to consider it. However, if the supplement does improve sport-specific performance, then athletes must analyze the pros and cons of supplementation.

(2)   Weigh the risks, benefits, and costsSupplements come with some baggage. They might have side-effects or safety concerns that must be known prior to starting them. They can also be costly, both monetarily and professionally. Loading up on an extensive supplement protocol could break your bank, but also opting for cheaper products could put your professional career at risk by failing doping tests. So, before you start, understand exactly what you’re taking. Then, consider if the benefits of supplementation truly outweigh the risks and costs.

Be sure to consider all the factors if you’re thinking about beta-alanine. It’s important to bring critical thought into your nutrition plan. Without it, we risk blindly following inaccurate or irrelevant claims and beliefs, and that’s when supplements become dangerous. If you have more questions, reach out to Preston Performance for a consult! We can discuss anything and everything that’s on your mind. We want to ease any hesitation or settle any inner disputes you might have. To anyone now sold on beta-alanine, good luck with your experience! I hope you’re a Responder and see all the benefits we expect. To athletes realizing beta-alanine isn’t for you, DON’T WORRY! We’ve got plenty of other ergogenic aid articles coming down the pipeline.


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