These three amino acids make up approximately one-­third of muscle protein, explains Kristin Koskinen, R. Research has even linked BCAA consumption to increased resistance to fatigue , reduced muscle damage , and increased muscle mass.

These amino acids may also help you bounce back faster after that track workout. So if you can consume BCAAs pretty easily through your diet, should you take supplements? The reality is, most people get enough BCAAs from the food they already eat, says Koskinen. In fact, a scientific review published in the Journal of the International Society of Sports Nutrition found that there is no evidence that BCAA supplementation alone helps with muscle protein synthesis.

Meanwhile, a systematic review and meta-analysis published in in the journal Amino Acids found that while BCAAs may help with muscle recovery by reducing delayed onset muscle soreness, the high variability in the studies included make it difficult to know whether BCAAs are efficient for untrained participants, when to take supplements, and whether higher dosage is a good idea.

Still some experts say that people with GI issues or those who have a hard time eating anything before early morning workouts could benefit. One small study backs up the benefits of pre-workout BCAAs. Published in The Journal of Sports Medicine and Physical Fitness in and involving 15 young men, researchers found that taking a BCAA before exercise reduced soreness after the workout.

How much BCAAs you would need is pretty individualized, says Auslander. before experimenting would help you figure out what might work for you.

However, while BCAAs might help you feel less fatigued during a workout or sore after a workout, they may not actually improve your performance. For example: Whey is a complete protein , with all nine essential amino acids that is also quickly digested and absorbed.

Before you start popping supplement pills or dropping any kind of powder into your water, talk to a registered dietitian who has experience working with runners. Remember that nutrients are better absorbed when they come from food, so upping your protein intake via whole, healthy foods should always be your first choice.

The Benefits of the Mediterranean Diet. Is the Keto Diet a Smart Choice for Runners? Foods That Cut Inflammation to Improve Performance. Symptoms of Magnesium Deficiency. Study: Cutting Sugar, Processed Meat Extends Life. To this end, a recent study [ 26 ] validated a variable high intensity protocol followed by a time to exhaustion TTE endurance capacity test namely high intensity endurance cycling test, HIEC as a reliable and sensitive method to assess both performance and fatigue, providing a stable platform for the comparative analysis of the effects of different nutritional interventions.

HIEC can be performed either at the beginning or at the end of training periods and protocols. In the present study, we applied HIEC to a 9-week program based on High Intensity Interval Training HIIT , a widely used protocol to improve specific variables of endurance performance [ 27 , 28 ].

It is worth noting that, to date, to the best of our knowledge, no study has tested the effects of the consumption of a commercially available and established BCAA-alanine-CHO based supplement on HIEC over a medium-long endurance training period. The second aim was to verify whether a prolonged supplementation may help participants to comply with the required training load during a 9w HIIT program with progressively increasing volume.

The participants were advised to maintain their dietary routine, and to abstain from using additional dietary supplements during the study period.

They were also instructed to refrain from all training activities except for the sessions included in the experimental design.

Subjects were asked to refrain from the consumption of alcohol, hypnosedative drugs and beverages containing caffeine on the 2 days prior to the trial. Stratification was used to ensure equal allocation by gender to each experimental condition.

BCAA and Ala content per single dose is within the range recommended by European Food Safety Authority and comparable to the dosage used in other studies [ 4 , 18 , 30 ]. The PL group ingested a non-caloric placebo that was identical in packaging, appearance and taste to the actual supplement.

Importantly, as verified by the qualified medical specialist P. Oxygen consumption was monitored breath-by-breath using a Cosmed K4b2 metabolimeter, COSMED, Rome, Italy and values of heart rate HR assessed with a Polar RS HR monitor, POLAR, Kempele, Finland were recorded continuously; VO 2max was calculated according to Robergs et al.

As already experimented in a previous study [ 36 ], and according to Seiler et al. RPE was determined with the 0—10 OMNI-cycle scale, which combines mode-specific pictorial illustrations with a numerical rating format, using a procedure described in the literature [ 40 , 41 ].

Participants were asked to point to their RPE on the OMNI-cycle scale, which was in full view at all times during testing. TTE was taken as a performance marker. Immediately after the incremental test,. On the experimental day, subjects in the first group arrived at the laboratory at The second group of the day arrived 2 h later in a fasted state.

The design of the experimental session is shown in Fig. Design of the experimental sessions at 1d and 9w. The experimental sessions were performed in the morning.

In the course of the HIEC, RPE was repeatedly evaluated as indicated by the arrows. Ammonia levels at T0, pre and post-HIEC were measured using a commercially available assay Sigma Ammonia Assay Kit, Sigma-Aldrich, USA. The serum blood levels of BCAA, Ala, total and free Trp were determined at T0, pre and post-HIEC, by HPLC according to Stocchi et al.

Thirty-six indoor cycling training sessions were performed over a 9w period see Fig. The training sessions were divided into three mesocycles, as follows:. Structure of training period: nine weeks divided into three mesocycles three weeks each. The frequency and the duration of the sessions are also indicated.

Key: VO 2max , maximal oxygen consumption; W LT1 and W LT2 , power at lactate thresholds; W peak , peak power; HIEC-T, high intensity endurance cycling test. The 32 subjects were divided in two groups of 16 and trained by two expert instructors with the aim of following the same training program.

Each session was choreographed based on conventional principles. warm-up, systematic high intensity interval exercise, and cool-down widely used in the indoor cycling community [ 46 ]. During the training sessions, the HR of each subject instructor included was monitored and recorded using a Polar Team Pack 2 POLAR, Kempele, Finland.

One hour before each training session, the subjects of the SU group ingested a single dose of FP, while the subjects of the PL group ingested the placebo. Briefly, the score for each zone is calculated by multiplying the accumulated duration in the zone by a multiplier for that particular zone e.

Finally, the mean TRIMP scores of each mesocycle performed by the SU and PL groups were compared. Descriptive statistics were performed using means and standard deviations. Homogeneity between groups was tested using the unpaired t - test. The time series of the RPE analysis were performed using the HIEC test values for each of the four conditions 1d SPR, 1d REC, 9w SPR, 9w REC comparing the PL and SU groups.

For each of the four conditions, differences between slopes and intercept SU vs PL were tested using the statistical approach according to Dupont and Plummer [ 49 ].

Furthermore, in all experimental conditions, SPR RPE values were plotted against delta RPE SPR - REC in order to verify the degree of recovery in REC steps. Two-way ANOVA with interaction was used in 1d and 9w conditions to test the association among group partnership SU vs PL and gender, used as predictive binary factors, and TTE, used as a dependent variable.

Partial eta-squared η 2 values were used as ES. VO 2max , W peak , W LT1 and W LT2 were compared between 1d and 9w training using ANOVA for repeated measures, using groups as a between categorical predictive factor.

According to Cohen [ 48 ], an η 2 ranging from 0. TRIMPs were compared between groups as the mean of sessions of each mesocycle. TRIMP comparison was performed using a two-way ANOVA with interaction, followed by the LSD post-hoc test.

Similarly, glucose levels were compared at different measurement times. Finally, CK, total BCAA, alanine, total Trp, free Trp, Trp:BCAA and ammonia levels were compared using a two-way ANOVA for repeated measures. CK levels were also plotted versus TRIMP values during HIEC, and correlation analysis was performed.

For total BCAA, alanine, total Trp, free Trp and Trp:BCAA, time was within factor t0, pre-HIEC and post-HIEC and group membership was between factor. All statistical analyses were performed using Excel or SPSS Anthropometric, metabolic and biomechanical variables of participants were assessed before the beginning of the experimental session as reported in Table 2.

No differences were found between the two groups in the tested parameters. Daily CHO, fat and protein intakes, supplemented vs placebo group were All these variables, namely VO 2max , W peak , W LT1 and W LT2 , were significantly different in pre vs post 9w training as shown in Table 3.

During the 10 SPR, each of them followed by a REC step, RPE showed an upward trend characterized by a sawtooth pattern in all the conditions tested. As expected, the RPE values reached the maximum at the end of the TTE step 11 points on OMNI cycle scale. prior to TTE phase were considered for further analyses data highlighted in grey box.

Perceived exertion rate RPE values versus session time; a - b whole RPE time series; c - d RPE values in sprint SPR steps at pre-training 1d and post training 9w stages, respectively; e - f RPE values in REC steps at 1d and 9w, respectively. Closed circles refer to SU and open circles to the PL group.

This would imply that in REC steps, the SU group showed a lower RPE Fig. This implies that in the REC steps, the SU group showed a systematically lower RPE Fig.

On the whole, RPE values increased linearly over the execution time of HIEC in both the SU and PL groups Fig. Notably, the extent of the increment was significantly lower in the SU group than it was in the PL group in all the conditions tested Fig.

That SU group experienced a more efficient recovery than the PL group,. a lower REC-associated RPE, which can be better appreciated in the scatter plots of Fig. RPE reduction after the completion of each REC step in the SU and PL groups.

The RPE differences are expressed as Delta RPE, which represent the difference between the RPE measured at the end of each SPR and at the end of its subsequent REC step. Delta RPE are plotted against the absolute RPE on the x-axis measured at the end of each corresponding SPR step. Panel a and b show 1d and 9 w, respectively.

Difference between the mean RPE scores of SU vs PL groups. Solid bars express the percent RPE differences between the SU and PL groups in the SPR phases and open bars, the percent RPE differences in the REC phases; RPE were measured during the 1d left and 9w right HIEC sessions.

The 1d SPR column was calculated from the data points in Fig. TTE values were determined and taken as reliable performance parameters [ 50 , 51 ]. TRIMP represents a recognized parameter to express the extent of training load [ 52 ].

Data are shown in Fig. Training loads in the PL and SU groups as a function of mesocycles and training progression. Bars represent the mean training impulse TRIMP associated with the corresponding mesocycle in the PL white columns and SU black columns groups standard deviations are reported.

Mesocycles and weeks are reported on the x axis. Dashed lines SU and solid lines PL were obtained using a 5-day moving average. In other words, CK levels were significantly higher only in the SU group in the post-HIEC at 9w, while in all the other conditions, no significant differences could be identified.

Creatine kinase CK serum blood levels. HPLC analysis of serum blood samples Fig. Branched chain amino acids [BCAA] serum blood levels. Panels a and b show analyses performed at 1d and 9w respectively. Values for the SU black bars and PL white bars groups are reported, with mean and standard deviations.

Pre- and post-HIEC plasma levels of total Trp and free Trp were also determined and are shown in Fig. Total and free Trp plasma concentrations. Trp levels were determined at pre-HIEC and at post-HIEC. Panels a and b show analyses performed at 1d and 9w, respectively. Key: pale grey bars show total Trp in the PL group; dark grey bars, the total Trp in the SU group; white bars, the free Trp in the PL group; black bars, the free Trp in the SU group.

Data are reported as means ± standard deviation. Regarding Trp:BCAA ratios, at pre-HIEC they were consistently higher in the PL group than they were in the SU group Fig. At 1d, notwithstanding the time-related increase in both groups pre- vs post-HIEC , the PL group was characterized by a higher ratio than the SU group; interestingly, at 9w a statistically significant increase could be found only in the PL group.

Free Trp to BCAA ratios. Free Trp and BCAA levels were determined and their ratios were then calculated in both the FP and PL groups. Trp:BCAA ratios before pre-HIEC and after HIEC test post-HIEC are shown. Panel a shows analyses performed at 1d and panel b those performed at 9w.

Values for the SU black bars and PL white bars groups are reported as means with standard deviations. Finally, serum ammonia levels at 1d were At 9w similar values were observed with T0 levels of Ala serum blood levels after SU or PL ingestion and post-HIEC.

a and b refer to the beginning 1d or the end 9w of the training period, respectively. Glycemia was determined prior to breakfast 4. No further significant difference between groups was observed post-HIEC 6. The effects of FP -an established, commercially available sports nutritional supplement containing BCAA, Ala and CHO - on RPE, performance and the capacity to sustain physical training were investigated in a group of 32 healthy young subjects enrolled in a randomized double-blind placebo-controlled trial.

Along with RPE and performance values, a number of relevant nutritional and biological parameters were also determined. Notably, to the best of our knowledge, this is the first study adopting a validated and reliable HIEC protocol [ 26 ] for these purposes.

Indeed, other protocols have been used to determine similar end-points in the past [ 20 , 53 ], but it is worth noting that they had not been previously and specifically validated. This finding indicates that BCAA are rapidly absorbed after oral ingestion of FP, and that their increased serum blood concentration is likely related to the above-mentioned effects on RPE, TTE and TRIMP.

Following the first intake, the SU group showed lower RPE values only in the HIEC REC phases, while a significant RPE reduction was found following a chronic 9w intake also in the high intensity SPR phases. Furthermore, both acute and chronic intake caused a significantly more rapid decrease in RPE observed between the SPR and corresponding REC phases compared to PL.

It is worth noting that, unlike previous studies on BCAA and RPE [ 14 , 54 ], by virtue of the particular design of the HIEC test, this is the first investigation in which RPE associated with SPR or with REC phases was separately quantitated. This allowed us to determine that FP significantly accelerated the reduction of RPE during the recovery phases compared to PL.

As regards Trp levels, we only found a slight although significant exercise-dependent variation in free-Trp between pre- and post-HIEC, an effect in line with the data reported and discussed by other Authors [ 55 , 56 ]. Our results indicate that serum blood circulating Trp:BCAA ratios increase after HIEC in PL, and that FP consumption invariably prevented this effect.

Similar qualitative and quantitative results have been observed in previous studies [ 14 , 30 ] on BCAA supplementation and RPE in exercising young adults. Under the conditions we observed in the PL group, namely an increased Trp:BCAA ratio, Trp is supposed to be more available for brain uptake, thus promoting an augmented synthesis of serotonin [ 23 ]; on the contrary, a significantly lower Trp:BCAA ratio, which we did observe in the SU group, is thought to antagonize brain Trp uptake, thus limiting serotonin synthesis and availability [ 57 ].

Since in our conditions Trp blood levels increase, some concern might be raised with regard to its conversion, through the kynurenine pathway, into correspondingly higher levels of the excitotoxic quinolinic acid and kynurenine [ 58 ]. However, as discussed by Fernestrom et al.

In addition, physical exercise has been shown to prevent per se the eventual brain entry of Trp-derived kynurenine [ 60 ] as well as to attenuate the activity of the kynurenine pathway [ 61 , 62 ]. Ammonia cerebral uptake and concentration are known to increase in humans during prolonged exercise [ 12 ], thus augmenting central fatigue by altering cerebral energy metabolism and neurotransmission [ 8 ].

However, although HIEC promotes an increase in serum ammonia levels, we did not find differences between the SU and PL groups at any of the considered time points T0, pre-HIEC and post-HIEC.

This finding, in keeping with data from the literature [ 15 ], might depend on the relatively low dose of supplemented BCAA. With regard to the higher [Ala] upon FP ingestion, we can only speculate on its relevance based on the literature. Supplemental Ala has been shown to exert a positive influence on the anaplerosis of the tricarboxylic acid cycle, on muscle glycogen storage, energy synthesis and on the regulation of ammonia metabolism, transport and excretion [ 63 , 64 ].

Along these same lines, although we have no direct evidence, higher [Ala] could exert a converging role in support of the effects on RPE observed herein. Regarding glycemia, we did not find any variation between the two groups in the glycemic values of pre- and post-HIEC tests, suggesting that the extra CHO of FP do not significantly modify blood glucose prior to or after testing compared to PL.

In light of these considerations, the CHO contribution to the functional and metabolic outcomes described thus far is probably limited. Finally, with respect to the possible direct effects of CHO on RPE, only in studies in which CHO were given during -and not prior to as in our case - endurance exercise have such effects been observed [ 66 ].

On the whole, it can be inferred that in our conditions CHO hardly affect RPE through direct central interactions. With regard to performance, most of the studies on BCAA-containing supplements have failed to find any significant improvements [ 54 , 67 ] nor did we find any differences in terms of relevant metabolic parameters VO 2max and Power at Lactate Thresholds between SU and PL, either upon single 1d or prolonged 9w supplementation.

However, even though TTE did not improve after the first, acute intake of FP, it did increase significantly following the 9w supplementation. This observation is in line with those of Kephart et al. Interestingly, the same study also reported a significant increase in serum blood [BCAA] and a consequent improvement in the circulating Trp:BCAA ratio, hence suggesting that performance enhancement could be related to a central fatigue-mediated mechanism [ 22 ].

Considering that our SU group did not show any improvement in metabolic parameters or free-fat mass not shown , we also suggest that the TTE increase might be related to the stable attenuation of RPE rather than to ergogenic or anabolic effects. Interestingly, at higher work volumes ca.

In this regard, it is worth considering that higher TRIMP expresses an increased ability to sustain exercise at high HR values, while lower TRIMP reflects the relative inability to exercise under the same conditions.

Several studies report that the inability of athletes to increase their HR for a given load is indicative of an overreaching state [ 68 , 69 ]. Again, in accordance with the serotonin theory of central fatigue, chronic elevation in brain serotonin levels has been causally associated with the development of an overtraining state and related symptoms, culminating in decreased performance [ 70 ].

Although it is mere speculation, the improved Trp:BCAA ratios afforded by FP supplementation could also explain the enhanced capacity to sustain higher training loads in SU athletes. BCAA supplementation, under specific circumstances high dosage,. However, despite the exhaustive protocol adopted, we did not find serum CK variations ascribable to muscle damage.

On the other hand, we found that after 9w of supplementation, the transient post-HIEC increase in CK was significantly higher in the SU group than it was in the PL group, an effect that could be accounted for by the higher training load of the SU group.

These results suggest that the transient CK increase in our conditions is not indicative of muscle damage, but is rather an expression of the higher training load [ 75 ].

On the whole, our data suggest that the higher TRIMP values found in SU subjects at 9w reflect their enhanced capacity to sustain training, whose volume may consequently increase over time leading to better performance than that achieved by PL subjects.

Reduction in RPE, which was observed from the very beginning of the test period, is likely to play a pivotal role in the progressively enhanced capacity to sustain higher training volumes.

The main limitation of the present study, as well as of similar ones, lies in the use of a multi-ingredient supplement, which makes it difficult to determine the relative impact of each component on the tested markers: as a consequence, ascertaining which of the ingredients had what effect or if there was a synergistic interaction among the ingredients remains an open question.

On the other hand, the strength of this study resides in the fact that it details a multi-technique experimental approach that could be applied, in the future, to directly compare the efficacy of formulations containing different constituents such as caffeine, electrolytes, β-alanine etc.

in attenuating RPE. This would be important because, at present, it is very hard to compare the effects of different sport supplements with different formulations on RPE because they have been studied using non-homogeneous experimental designs and approaches [ 76 ].

Although it was not possible to specifically address mechanistic issues, the effects we observed are in keeping with the theory of RPE sensitivity to serum blood Trp:BCAA ratio, while the contribution of metabolic effects seems negligible.

The prolonged intake of FP, which promotes a reduction in RPE and recovery times, can enhance the capacity to sustain higher training loads and ultimately improve endurance performance.

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