Havemann et al. Overall, differences in the performance times for the km time trial TT were not statistically significant, although the mean performance on the high-carbohydrate trial was 3 min 44 s or ~2. While there was no difference between trials with regard to the 4-km sprint times, performance of the 1-km sprints was significantly impaired in the LCHF-adapted trial in all subjects, including the three subjects whose overall km TT performance was faster than in their high-carbohydrate trial.

Power outputs during 1- and 4-km sprints undertaken within a km self-paced cycling time trial after a 6-day high-carbohydrate diet and 5 days of a low-carbohydrate high-fat diet followed by 1 day of a high-carbohydrate diet fat-adapt [ 1 ].

FAT-adapt, not significant. Values are means ± standard deviation for eight well-trained cyclists. Reproduced from Havemann et al. HCHO high carbohydrate. In an investigation of possible mechanisms to explain the performance outcomes associated with the LCHF-adaptation and carbohydrate-restoration model, we examined muscle metabolism at rest, during sub-maximal exercise, and after an all-out 1-min sprint following the usual dietary treatment Fig.

In comparison with the control trial high-carbohydrate diet , we found that adaptation to the LCHF diet and subsequent restoration of muscle glycogen was associated with a reduction in glycogenolysis during exercise, and a reduction in the active form of pyruvate dehydrogenase PDHa at rest, during submaximal cycling, and during sprint cycling.

Explanations for the down-regulated activity of this enzyme complex responsible for linking the glycolytic pathway with the citric acid cycle included the observed post-sprint decrease in concentrations of free adenosine monophosphate AMP and adenosine diphosphate ADP and potentially an up-regulation of PDH kinase PDK activity, which has previously been observed in association with a high-fat diet [ 47 ].

Values are means ± standard error of the mean for seven well-trained cyclists. Reproduced from Stellingwerff et al. HCHO high carbohydrate, PDH pyruvate dehydrogenase, PPO peak power output, VO 2 max maximal aerobic capacity.

Key interpretations by this author from the literature on adaptation to an LCHF conducted up until are summarized below:. Exposure to an LCHF diet in the absence of ketosis causes key adaptations in the muscle in as little as 5 days to retool its ability to oxidize fat as an exercise substrate.

Adaptations include, but are not limited to, an increase in IMTG stores, increased activity of the hormone-sensitive lipase HSL enzyme, which mobilizes triglycerides in muscle and adipose tissue, increases in key fat-transport proteins such as fatty acid translocase [FAT-CD36] and carnitine-palmitoyl transferase CPT for extended review, see Yeo et al.

Together, these adaptations further increase the already enhanced capacity of the aerobically trained muscle to utilize endogenous and exogenous fat stores to support the fuel cost of exercise of moderate intensity. Rates of fat oxidation during exercise may be doubled by fat-adaptation strategies.

These muscle-retooling activities stimulated by fat adaptation are sufficiently robust that they persist in the face of at least 36 h of aggressive dietary strategies to increase carbohydrate availability during exercise e.

Although the increased carbohydrate availability reduces rates of fat oxidation compared with fat adaptation alone, fat utilization remains similarly elevated above comparative rates in the absence of fat adaptation.

In addition to up-regulating fat oxidation at rest and during exercise, exposure to an LCHF diet down-regulates carbohydrate oxidation during exercise. Direct [ 34 , 42 , 45 ] and indirect [ 45 ] techniques of measuring the source of changes in substrate utilization show that changes in utilization of muscle glycogen, rather than blood glucose or exogenous glucose, account for the change in carbohydrate use.

The reduction in glycogen use persists in the face of glycogen supercompensation [ 45 ] and high-intensity exercise [ 46 ], noting that it is robust and independent of substrate availability. A down-regulation of PDH activity explains at least part of the impairment of glycogen utilization as an exercise fuel [ 46 ], representing a decrease in metabolic flexibility.

Despite the enhanced capacity for utilization of a relatively limitless fuel source as an exercise substrate, fat-adaptation strategies with or without restoration of carbohydrate availability do not appear to enhance exercise capacity or performance per se. Several inter-related explanations are possible for the failure to observe benefits:.

Type II statistical error: failure to detect small but important changes in performance due to small sample sizes [ 34 ], individual responses [ 42 , 45 ], and poor reliability of the performance protocol. While this explanation often looks attractive [ 43 ], in some cases, further exploration and enhanced sample size increases confidence in the true absence of a performance enhancement [ 43 ].

Benefits are limited to specific individuals: characteristics of individuals who may respond to fat-adaptation strategies include carbohydrate-sensitive individuals who are subjected to scenarios in which carbohydrate cannot be consumed during exercise. This is likely to be due to the impairment of the muscle glycogen utilization needed to support high work rates, even in scenarios where strategies to achieve high carbohydrate availability are employed.

On the basis that conventional competitive sports generally provide opportunities to achieve adequate carbohydrate availability, that fat-adaptation strategies reduce rather than enhance metabolic flexibility by reducing carbohydrate availability and the capacity to use it effectively as an exercise substrate, and that athletes would be unwise to sacrifice their ability to undertake high-quality training or high-intensity efforts during competition that could determine the outcome of even an ultra-endurance sport, this author decided to abandon a research and practical interest in fat-adaptation strategies.

Given the recent escalation in the promotion of LCHF diets for sports performance, it could be assumed that the last decade has seen the publication of a considerable number of studies with clear evidence of benefits to sports performance following the implementation of fat-adaptation strategies.

Yet, to the knowledge of this author, only two new investigations of LCHF diets in athletes have appeared in the peer-reviewed literature since [ 49 , 50 ]. These studies, summarized in Table 2 , fail to show performance benefits associated with a ketogenic LCHF diet, although there is evidence of a small but favorable reduction in body fat levels.

Nevertheless, there are some peculiarities with the design or methodologies of these studies, including the failure of one study to achieve the carbohydrate restriction typically associated with the ketogenic LCHF diet, and they have failed to become widely cited, even by supporters of the LCHF movement.

Rather, the current interest in chronic application of LCHF eating by athletes appears to be driven by enthusiastic discussion in lay and social media by mostly non-elite athletes of sporting success following experimentation with such diets as well as a range of outputs from several sports scientists who are researchers and advocates of this eating style [ 3 — 8 ].

It is uncertain whether there is a cause—effect relationship between these sources or the direction of any relationship , but the fervor merits attention. In the absence of compelling new data, the reader is alerted to several elements in the discussions that are positive and some that are concerning:.

Peer-reviewed publications from the key scientific protagonists of the LCHF movement [ 3 , 5 , 6 ] generally show measured and thoughtful insights, based on a re-examination of previously conducted studies, personal experiences, anecdotal observations from the sports world, and the general interest in tackling modern health problems with the LCHF approach [ 51 , 52 ].

In these forums, the discussion points include the lack of evidence and equivocal outcomes of research to support the performance benefits of LCHF but also theoretical constructs around potential benefits to metabolism, muscle, and brain function, inflammatory and oxidative status, and body composition management.

While there are some suggestions that a larger group of athletes might benefit from an LCHF approach, the general tone is that further investigation of these theories is required [ 3 — 6 ]. The apparent caution expressed in peer-reviewed publications is generally not present in other outputs from the same authors.

The differences between these viewpoints can be confusing, as is the misrepresentation of the physiological requirements of competitive sports see Sect. Many of the theorized benefits from the LCHF diet are claimed to come from the adaptation to high circulating levels of ketone bodies, which provide an additional fuel source for the brain and muscle as well as achieve other health and functional benefits [ 5 , 6 ].

The amount of energy that can be provided by ketones as an exercise substrate has been neither calculated nor measured, making it impossible to verify this claim.

The time required to achieve optimal adaptation and, therefore, the period that requires investigation in new studies is claimed to be at least 2—3 weeks, with at least 1 week required before the feelings of lethargy and reduced exercise capacity abate [ 5 , 6 ].

With such chronic keto-adaptation, it is considered unnecessary to consume carbohydrate during exercise, or perhaps to consume it in small amounts [ 5 , 6 ]. As has been discussed in this review, the current evidence for these claims is equivocal and mostly anecdotal.

Until or unless further research is undertaken, we are unlikely to resolve any of the current questions and claims. The role of non-ketogenic LCHF diets is not clear.

The current literature on LCHF diets is relentless in promoting misunderstanding or misinformation on the current guidelines for athletes in relation to carbohydrate intake in the training or competition diet.

It would benefit sports nutrition for researchers and practitioners to show mutual respect in recognizing the evolution of new ideas and the replacement of old guidelines with new recommendations [ 53 ]. Indeed, modern sports nutrition practitioners teach athletes to manipulate their eating practices to avoid unnecessary and excessive intakes of carbohydrates per se, to optimize training outcomes via modification of the timing, amount and type of carbohydrate-rich foods and drinks to balance periods of low- and high-carbohydrate availability and to adopt well-practiced competition strategies that provide appropriate carbohydrate availability according to the needs and opportunities provided by the event and individual experience [ 14 , 54 — 57 ].

This author and others continue to undertake research to evolve and refine the understanding of conditions in which low carbohydrate availability can be tolerated or actually beneficial [ 58 , 59 ].

However, we also recognize that the benefits of carbohydrate as a substrate for exercise across the full range of exercise intensities via separate pathways [ 16 ], the better economy of carbohydrate oxidation versus fat oxidation ATP produced per L of oxygen combusted [ 60 ], and the potential CNS benefits of mouth sensing of carbohydrate [ 61 ] can contribute to optimal sporting performance and should not be shunned simply because of the lure of the size of body fat stores.

Considering that athletes might best benefit from a range of options in the dietary tool box is likely to be a better model for optimal sports nutrition than insisting on a single, one-size-fits-all solution. Havemann L, West S, Goedecke JH, et al.

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This is in line with a the trend towards an increased FAO without affecting the overall POMS score of total mood disturbance in both resting and exercise conditions found in this study Table 3.

Reinbach et al. The acute effects found on appetite in the present study are likely to have resulted from the active ingredients within the supplement we tested.

Only limited data are available to confirm these effects, with one study reporting Yerba Maté effectiveness on appetite and satiety markers glucagon-like peptide 1 GLP-1 and leptin in high-fat diet-fed mice [ 24 ].

Long term studies are needed to establish the appetite reduction effect of multi-ingredient weight loss products. It may not be possible to compare the bioavailability of the several active ingredients within this multi-ingredient product during exercise.

However, it is reasonable to actuate the metabolic outcomes based on understanding of the well-established concepts in the area of exercise metabolism [ 15 , 18 , 27 ].

Comparing the various effects of different commercially available multi-ingredient products during exercise may not be possible, even though their effectiveness has been comprehensively reviewed for weight loss [ 29 ]. It remains to be investigated how single ingredients and their concentrations within the multi-ingredients can be effective for augmenting weight-loss outcomes during exercise.

The study focused on the combined effects of the multi-ingredients, but the individual ingredients were not studied here. While it is likely that they promoted some of the beneficial effects found, this study did not demonstrate whether they have worked synergistically.

Future research may investigate the synergy of the multi-ingredients within such a fat-loss product. The present study demonstrated a potential acute effectiveness for ingesting SHRED on fat-loss outcomes after at least min rest and during exercise at workloads corresponding to an individualized Fatmax-intensity.

There is a trend of augmented FAO in SHRED compared with PL as indicated by moderate effect size in FAO. Fatmax exercise intensities are known markers for effective aerobic exercise prescription. Therefore, the multi-ingredient effects of SHRED on FAO, combined with a decreased perception of effort and a trend towards an improved satiety, suggest a potential acute effectiveness in improving exercise-related fat loss outcomes.

Future research may investigate the chronic effects of multi-ingredient fat-loss products when combined with exercise on weight loss outcomes. World Health Organization global strategy on diet, physical activity and health Blanck HM, Khan LK, Serdula MK.

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Phytother Res. Download references. Division of Sport and Exercise Science, School of Social and Health Sciences, University of Abertay, Bell Street, Dundee City, DD1 1HG, United Kingdom.

Centre for Sport Science and Human Performance, School of Science, University of Greenwich, Medway Campus, Central Avenue, Chatham Maritime, Kent, ME4 4TB, London, United Kingdom. Clinical Research Institute, Texas Tech University Health Sciences Center, Lubbock, TX, USA.

You can also search for this author in PubMed Google Scholar. Correspondence to Ahmad Alkhatib. Funding for this study was provided to the University of Greenwich through an Unrestricted Educational Grant through The International Society of Sport Nutrition ISSN sponsored by MusclePharm Corporation.

No payment or any financial reward has been received by the authors in relation this study. All authors declare no conflict of interests. AA conceived the study idea, designed and coordinated the study, participated in the data analysis, and drafted the full manuscript.

MS collected the data, and contributed to the study design, coordination, data analysis and manuscript drafting. EL participated in the data analysis, and drafting the manuscript. FN contributed to the study design, coordination, data analysis, and drafting the manuscript.

All authors approved the final manuscript. Open Access This article is distributed under the terms of the Creative Commons Attribution 4. Reprints and permissions. Alkhatib, A. et al. J Int Soc Sports Nutr 12 , 44 Download citation. Received : 07 September Accepted : 22 November Published : 25 November Anyone you share the following link with will be able to read this content:.

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Download PDF. Download ePub. Abstract Background Achieving fat-loss outcomes by ingesting multi-ingredient mixtures may be further enhanced during exercise. Methods Following institutional ethical approval, twelve healthy recreationally active participants, five females and seven males, were randomized to perform two separate experimental ergometry cycling trials, and to ingest 1.

Results FAO increased in SHRED from Pre1 to Pre2 [0. Background Even though an improved diet and exercise are known to be the best tools to reduce excess body weight and reverse the associated health risks [ 1 ], the popularity of weight-loss aids have increased as a fast method to obtain the desired outcomes.

Enhancing exercise dependent fat-loss, such as metabolic and psychomotor outcomes of Fatmax intensities, satiety and mood state may be achieved by administering a combination of effective weight-loss ingredients such as those contained in a commercially available products, including Green Tea Extract, Yerba Maté, Guarana Seed Extract, Anhydrous caffeine, Saw palmetto, Fo-Ti, Eleuthero root, Cayenne Pepper, and Yohimbine HCI.

Methods The study followed a double-blind crossover repeated measures controlled design.

the effect of the GI of high carbohydrate diets on energy metabolism and running capacity have been investigated The authors concluded that the GI had no influence on rates of fat oxidation. Taking metabolic adaptations to HFLC diets under consideration, 5 days might be insufficient for a LGI diet to have an impact on the metabolic response 9 , A long-term effect has only been investigated in a study by Durkalec-Michalski et al.

In contrast to our findings, the LGI diet over 3 weeks resulted in a slight downregulation of fat oxidation during exercise However, in the study by Durkalec-Michalski et al. Furthermore, the decrease in RER values was not statistically significant and did not reach the MID in the present study.

The LGI intervention seemed to have a smaller impact on metabolic adaptations than the HFLC diet. The up-regulating signals of fat oxidation are low insulin concentration and increased concentrations in plasma free fatty acids 2 , 3.

A direct comparison between four meals, each different in the amount and GI of the ingested carbohydrates, has shown that both high fat groups were associated with the highest postprandial free fatty acid and lowest insulin concentrations. The lowest free fatty acid concentrations were in the group consuming a low glycemic carbohydrate-rich meal.

Furthermore, postprandial insulin response was lower in the high carbohydrate low GI group compared to the high carbohydrate high GI group Consequently, the abovementioned adaptation processes might be less in a high carbohydrate low glycemic diet compared to a HFLC diet due to the different impact on postprandial free fatty acid and insulin concentrations.

The nutritional impact on fat metabolism might also be reflected by the circulating glucose concentrations. Fasting glucose plasma concentrations dropped in the LGI-G to a significant and MID relevant extent.

Changes in the HFLC-G seemed to be less pronounced, potentially as a consequence of relatively low baseline values compared to the other groups. During the post-intervention, incremental test glucose concentrations are lower at the same exercise intensity as in the unconditioned pre-values state in both LGI-G and HFLC-G.

This is probably related to a stimulation of fat oxidation under resting conditions and during exercise The results of the HGI-G seemed to be controversial. The increased RER at rest in the HGI-G indicates an elevated metabolization of carbohydrates under resting conditions.

In addition, the lactate concentration increase was clinically relevant under pre-exercise condition. Despite increased lactate concentrations during the incremental test, it seems that there is an improved fat metabolism -decreased glucose and lactate values- in the submaximal cycle test.

It had previously been described that carbohydrates prior to exercise appear to be beneficial to performance 1. Hence, the slightly decreased carbohydrate metabolism in the submaximal test might be partly explained by the increased lactate threshold over the time as a possible adaptation in response to enhanced performance.

As a result, at post-intervention, the participants performed the test closer to their lactate threshold compared to baseline. The current investigation also observed an improvement in body composition due to a decrease in fat mass following the 4-week LGI or HFLC diet on the level of significance and MID.

It is not assumed that the present results can be attributed to the differences in energy intake between groups. Despite the significant difference in proportions of nutrients, the mean energy intake was equivalent between groups with an energy add-on of kcal in the HFLC-G.

According to the findings of Hall et al. There is evidence that athletes can improve their body composition by a high fat in particular ketogenic diet 42 — Low carbohydrate diets compared with control diets have been suggested to be relatively more effective in body weight management.

However, the benefits of a low carbohydrate diet can be rather attributed to the relatively high protein content, but not the relatively lower carbohydrate content 45 , In a recent study with athletes, different approaches high vs.

low fat but similar protein intakes resulted in a similar change of body composition mean loss in body fat was 1. These are in accordance with a meta-analysis examining the impact of different diet types in obese or overweight people Data from the meta-analyses of the Cochrane Database of Systematic Reviews suggest that a low glycemic diet without energy restriction results in a significantly greater decreased fat mass and an increased fat free mass compared with a high glycemic or even high fat and energy restricted diet Although low glycemic diets seem to promote weight loss and metabolic improvements in obese and overweight adults 48 , research about the impact of the GI on body composition in endurance athletes is limited.

A recent study by Durkalec-Michalski et al. has shown that consuming a low glycemic diet led to a change in body composition.

In particular, a statistically significant reduction in body mass Physiologically, the significant changes in body composition in the present investigation might be explained by changes in fat oxidation and a more balanced carbohydrate metabolism as a potential consequence of the altered amount and quality of ingested carbohydrates.

Despite an improvement in fat metabolism and body composition, there is a growing body of evidence that these changes induced by ketogenic or non-ketogenic HFLC diets are not in association with improved endurance performance, aerobic capacity and peak performance in particular 9 , 32 , 50 , 51 , due to an impaired carbohydrate provision during higher intensities 2.

This assumption is supported by the changes in time to exhaustion in the present investigation. Furthermore, HFLC diets seem to be impractical and accompanied by side effects that include fatigue, headaches, poor concentration, lethargy, gastrointestinal discomfort, nausea, and unintentional weight loss.

One reason might be an insufficient proliferation of essential micronutrients and fibers and glycogen depletion which might be a cause of impaired concentration and hence the neuromuscular connection 9 , The values of the VAS scores of all categories decreased in all groups, indicating that the participants got familiar with the respective dietary concepts.

In general, none of the groups experienced clinically relevant elevated VAS scores. Mild symptoms can be defined by a score of 5 to 45 mm on the VAS This might be explained by the fact that endurance subjects tolerate the effects of a high-fat diet better than untrained individuals during exercise In addition, according to the nutritional protocols, an impaired delivery of minerals in the HFLC group was not expected.

However, only the LGI-G and HGI-G have shown an improvement in VAS scores of the subscale activity and gastrointestinal comfort on a statistical or MID level with a superior effect in the LGI-G. These results might be associated with impaired training sessions in the HFLC-G since higher intensity levels could not be reached without the provision of carbohydrates 2.

Furthermore, the advantage of LGI diet over HFLC and HGI diets might be in the choice of carbohydrates. A LGI diet is predominantly characterized by high-fiber and plant-based foods. This has shown to be associated with reduced fatigue, a strengthened immune system, and an improved ability to regenerate through the increased supply of micronutrients, essential fatty acids and amino acids, and low postprandial glucose concentrations Moreover, controlled clinical trials demonstrated that low glycemic foods have a positive impact on digestive conditions, such as gastroesophageal reflux disease or the irritable bowel syndrome, due to high fiber content 56 , It can be assumed that the present results can be attributed to the implementation of nutritional patterns.

According to the analysis of the nutritional protocols, the participants' dietary intake reflected the specified intake of carbohydrates and fats in the respective group. While the HGI-G had a higher percent and total carbohydrate intake, the LGI-G showed a higher carbohydrate intake on a g-per-kg-body-weight basis.

The current guidelines for endurance athletes during training on the competition level are 6—10 g carbohydrates per kg body weight and day.

These recommendations do not address the GI of the ingested carbohydrates The participants of the current investigation were non-elite athletes with a training workload of 3—5 sessions per week. In both groups, the carbohydrate intake seems to be sufficient since recommendations are 5—7 g carbohydrates per kg bodyweight and day for general training needs Nevertheless, increasing the carbohydrate intake to 6—10 g carbohydrates per kg body weight and day would be an interesting approach in future studies with high trained endurance athletes.

The carbohydrate upper limit of 50 g per day in the HFLC-G was based on the current focus of carbohydrate-restricted diets 9. This trial has some limitations. It has to be mentioned that the changes in fat and carbohydrate oxidation were not measured directly but extrapolated from the lactate diagnostics.

However, it is reported that measuring blood lactate is an effective way to estimate the rates of fat and carbohydrate oxidation Furthermore, using the values of the spiroergometry to confirm the results from the lactate diagnostic during the incremental test has to be taken with caution since values for VO 2 are overestimated by a step compared to a ramp incremental test When taking the impact of the nutritional concepts into account, limitations of the self-reported protocols might entail an over or underreporting of the consumed foods Moreover, recommendations for the macronutrient intake based on the body weight seems to be more accurate than percentage values to determine nutritional guidelines for endurance athletes.

Future studies with a larger sample size should include different sex groups and pre-exercise nutritional conditions to state practical use of high fat vs. high carbohydrate diets. Furthermore, the analysis of the muscle glycogen would be helpful for a better interpretation of the energy supply 9.

Ultrasonic assessment can be used to quantify glycogen content in the skeletal muscle In conclusion, the effect of the LGI diet was a decrease in lactate concentrations under resting and submaximal exercise conditions, while HFLC diet resulted additionally in decreased RER values.

However, these lower adaptations in the LGI-G seem to be beneficial in terms of an enhanced metabolic flexibility, since an increased carbohydrate metabolism was unaffected during higher intensities, while the utilization of fats was facilitated during submaximal exercise due to decreased plasma lactate concentrations.

Despite the positive impact on the fat oxidation and body composition, following a HFLC diet might have a negative effect on exercise performance due to the lack of carbohydrate provision at higher intensity levels.

In addition, there might be negative long-term health consequences due to the high fat content and decreased intake of essential micronutrients. The HGI-G changes in metabolism might impair the ability to effectively use fats and carbohydrates during different exercise intensities.

Taking these findings together, the implementation of a LGI diet leads to a more flexible fat and carbohydrate metabolism after 4 weeks of intervention in contrast to a HFLC or HGI diet, which might be of advantage, particularly during strenuous endurance exercise.

After the study was finished, DZ started as a researcher in the Collagen Research Institute, Kiel. The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation. DZ, HF, AG, and DK designed the study. DZ, HF, and DK were responsible for data acquisition and performed the analysis.

All authors read and approved the final version of the manuscript. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers.

Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher. We would like to thank all the participants and the staff of the University of Freiburg who supported us with the examination.

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Exclusion criteria were as follows: A History of any cardiovascular or respiratory disease, hypertension, liver or kidney disease, musculoskeletal or neuromuscular or neurological disease, autoimmune disease, cancer, peptic ulcers or anemia.

C Consuming any ergogenic aid or above habitual caffeine consumption rate mg. All Participants refrained from taking any supplements for the duration of the study and were instructed to refrain from strenuous exercise or alcohol and caffeine consumption for at least 24 h before each test.

Participants have also completed a 3-day hr food diary with details about serving amounts for breakfast, lunch, dinner, snacks and additional meals. All participants reported to the Physiology Laboratory on three separate occasions followed by 3 h fasting state in the first session, and 12 h overnight fast in the second and third sessions.

Each testing session between and am was separated by at least three days within two weeks period. During the second and third visits, after assessment of body composition, participants were randomized to ingest 1.

Three capsules with similar coatings of either SHRED or PL were placed within an empty water cup and taken in the same way with a ml of water. The SHRED capsules contained Green Tea Extract, Yerba Maté, Guarana Seed Extract, Anhydrous caffeine, Saw palmetto, Fo-Ti, Eleuthero root, Cayenne Pepper, and Yohimbine HCI.

The thermogenic ingredients per capsule included approximately 70 mg of green tea leaf, 50 mg caffeine anhydrase, and mg of Guarana seed extract. The exact content and other ingredients are in a proprietary blend.

Immediately following the anthropometric and body composition assessments, and ingestion, participants rested for min in a semi recumbent position in quiet laboratory condition.

Resting measurements involved heart rate HR , blood pressure BP [systolic SBP and diastolic DBP ] and RMR. Additionally, mood state was assessed just after the ingestion min before exercise , immediately pre and post exercise. Perception of hunger was assessed every 30 min after the ingestion, immediately pre and post exercise.

Body mass BM and height were assessed, on a standard scale and stadiometer. Participants were tested wearing only tight fitting clothing swimsuit or undergarments and an acrylic swim cap.

Thoracic gas volume was estimated for all subjects using a predictive equation integral to the Bod Pod® software.

The calculated value for body density was used in the Siri equation [ 26 ] to estimate body composition. The complete body composition measurement was performed twice.

If the two tests were not within the 0. All participants followed a ramp exercise cycling protocol using an electromagnetically braked cycling ergometer Schoberer Rad Messtechnik, SRM, Ergo, Julich, Germany during their first visit.

Similar verbal encouragement was provided to all participants throughout the exercise tests. The cycling ergometer was calibrated before use. The cycling positions that were taken in the first test were re-applied in the following visits. The following two visits involved the participants to follow a 30 min exercise cycling test at their individually determined Fatmax intensity.

Additionally, the heart rate HR was measured continuously Polar Sporttester, Polar Electro, Finland and the rate of perceived exertion RPE using the Borg scale 6—20 was measured every 3 min during all tests.

The metabolic data of FAO and CHO were estimated using the stoichiometric indirect calorimetry equations Eqs. The FAO during exercise was determined based on averaging the last twenty min of the 30 min. Fatmax g. Profile of mood state POMS questionnaire was analyzed for total mood disturbance total score, calculated for each participant by adding scores for Tension, Depression, Anger, Fatigue and Confusion and subtracting your Vigor score [ 28 ].

Hunger scale 1—10 scores was used to indicate a satiety score, with a score of one being starving and ten being stuffed. All data were described as means and standard deviations. FAO, CHO oxidation, and POMS questionnaire, were analyzed with 2x3 repeated measures ANOVA, to compare repeated conditions SHRED vs.

PL over time first hour pre, second hour pre, and post-exercise. The same procedure was used with Hunger Scale considering six time points pre, every 30 min during exercise, and post , with Heart Rate and RPE considering 11 time points rest, and every 3 min , and RPE considering ten time points every 3 min.

Post-hoc calculations were adjusted with Bonferroni method. Significance level was set at 0. Fatmax determined from the baseline assessment was 0. Significant interaction [F 9.

However, significant differences were found in the nine measures taken every 3 min during exercise p values: 0. Table 3. The present study is the first to demonstrate an acute effectiveness of a multi-ingredient supplement, SHRED-Matrix for exercise-related metabolic outcomes.

Findings include an enhanced FAO during exercise combined with an enhanced perceived exertion and improved side-effects associated with satiety, often reported with weight-loss supplements [ 9 , 29 ]. Ingesting a dosage of 1. These effects on substrate utilization were combined by a significant improvement in the rate of perceived exertion throughout the exercise duration, and a trend towards a decrease in the perception of hunger with SHRED and a significantly higher satiety scores at 30 min following the ingestion Table 3.

These combined effects of SHRED before and during exercise on metabolism, satiety and perceived exertion were independent of mood state, which was unchanged, and suggest a potential role for SHRED in enhancing exercise-related fat-loss outcomes.

There has been a surge in research into the potential weight loss effects for combining a number of ingredients in the present fat-loss product, in order to maximize their effectiveness. For example, Hoffman et al. The increased reliance on FAO at rest in SHRED compared with PL found in the present study support the thermogenic role of these multi-ingredients in both products.

Exercising at this intensity reflects an increased reliance on FAO as a fuel source and less reliance on CHO [ 15 , 18 ]. Although, the condition SHRED vs. PL effects were not significant based on the ANOVA main effects, there was a medium effect size for the condition in favor of SHRED from Pre to Post exercise.

The trend in an enhanced FAO was supported by a reduced perception of exertion Table 3. To our knowledge, this is the first study to demonstrate a potentially augmented FAO at constant load exercise 30 min corresponding to Fatmax, following the ingestion of such a multi-ingredient product, which implies a favorable exercise-related fat loss, due to a further increase in the reliance on FAO beyond that when exercising alone.

It is likely that the multi-ingredients contained within the presently tested SHRED ingredient Green Tea Extract, Yerba Maté, Guarana Seed Extract, Anhydrous caffeine, Saw palmetto, Fo-Ti, Eleuthero root, Cayenne Pepper, and Yohimbine have had joint metabolic effectiveness in increasing the reliance on FAO, which can be further augmented during exercise found in the present study.

Caffeine is perhaps the most studied single supplement for its effects on exercise performance for almost four decades [ 31 ]. Combining caffeine with other ingredients such as tea catechins in green tea, which promote energy expenditure [ 32 ] and caffeoyl derivatives e.

chlorogenic acid, caffeic acid phytosterols and saponins in Yerba Maté, which promote fat metabolism [ 23 ], Capsaicinoids in Cayenne pepper, which promote satiety [ 33 ] and the natural alpha-2 antagonist, yohimbine which is considered to promote sympathetic activity by central and peripheral mechanisms to promote fat oxidation [ 22 , 34 ].

Combining a mixture of previously known effective active ingredients may explain a number of resulting metabolic, neuromuscular, and hormonal changes that have resulted in increased energy expenditure, fat metabolism, and exercise performance enhancement [ 5 , 9 , 10 ].

RMR and EE has been reported to increase significantly at 60— min following ingesting products containing Yohimbine, green tea and caffeine, in the form of multi-capsules [ 22 ] and within an energy drink [ 35 ]. This resting duration is similar to the min resting period used in the present study.

It has been reported that green tea extract rich in catechin polyphenols and caffeine increases h energy expenditure and fat oxidation at rest [ 32 ]. Similar thermogenic effects at rest have been reported from ingesting Green tea [ 32 , 35 - 37 ], Caffeine [ 32 , 38 ], and Citrus aurantium [ 39 ], all contained within the SHRED supplement that have been used in the present study.

It is reasonable to suggest that active ingredients combined in SHRED can be responsible for alleviating hunger, enhancing satiety and possibly psychomotor-related mood state response [ 8 , 9 , 11 , 12 ].

Cayenne pepper, Yerba Maté, green tea, guarana, all can reduce appetite and energy intake, and improve mood state [ 24 , 40 , 41 ]. For example, Campos et al. Outlaw et al. However, they reported a significant increase in both resting metabolic rate and energy expenditure.

This is in line with a the trend towards an increased FAO without affecting the overall POMS score of total mood disturbance in both resting and exercise conditions found in this study Table 3. Reinbach et al. The acute effects found on appetite in the present study are likely to have resulted from the active ingredients within the supplement we tested.

Only limited data are available to confirm these effects, with one study reporting Yerba Maté effectiveness on appetite and satiety markers glucagon-like peptide 1 GLP-1 and leptin in high-fat diet-fed mice [ 24 ]. Long term studies are needed to establish the appetite reduction effect of multi-ingredient weight loss products.

It may not be possible to compare the bioavailability of the several active ingredients within this multi-ingredient product during exercise. However, it is reasonable to actuate the metabolic outcomes based on understanding of the well-established concepts in the area of exercise metabolism [ 15 , 18 , 27 ].

Comparing the various effects of different commercially available multi-ingredient products during exercise may not be possible, even though their effectiveness has been comprehensively reviewed for weight loss [ 29 ].

It remains to be investigated how single ingredients and their concentrations within the multi-ingredients can be effective for augmenting weight-loss outcomes during exercise. The study focused on the combined effects of the multi-ingredients, but the individual ingredients were not studied here.

While it is likely that they promoted some of the beneficial effects found, this study did not demonstrate whether they have worked synergistically.

Future research may investigate the synergy of the multi-ingredients within such a fat-loss product. The present study demonstrated a potential acute effectiveness for ingesting SHRED on fat-loss outcomes after at least min rest and during exercise at workloads corresponding to an individualized Fatmax-intensity.

There is a trend of augmented FAO in SHRED compared with PL as indicated by moderate effect size in FAO. Fatmax exercise intensities are known markers for effective aerobic exercise prescription.

Therefore, the multi-ingredient effects of SHRED on FAO, combined with a decreased perception of effort and a trend towards an improved satiety, suggest a potential acute effectiveness in improving exercise-related fat loss outcomes.

Future research may investigate the chronic effects of multi-ingredient fat-loss products when combined with exercise on weight loss outcomes. World Health Organization global strategy on diet, physical activity and health Blanck HM, Khan LK, Serdula MK. Use of nonprescription weight loss products.

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