RESUMO

The aim of this study was to evaluate the influence of sodium bicarbonate (SB) supplementation on physical performance, neuromuscular and metabolic responses during CrossFit® exercise. Seventeen Advanced CrossFit®-trained athletes completed the randomized, double-blind, placebo-controlled crossover protocol consisting of four visits, including two familiarization sessions and two experimental trials separated by a 7-day washout period. Participants supplemented 0.3 g/kg body mass (BM) of SB or placebo 120-min prior to performing the CrossFit® benchmark Fran followed by 500 m of rowing. SB improved time to complete Fran compared to PLA (291.2 ± 71.1 vs. 303.3 ± 77.8 s, p = 0.047), but not 500 m rowing (112.1 s ± 7.9 vs. 113.2 s ± 8.9 s, p = 0.26). No substantial side-effects were reported during the trials. This study showed that SB improved CrossFit® benchmark Fran performance, but not subsequent 500-m rowing. These data suggest that SB might be an interesting supplementation strategy for CrossFit® athletes.

RESUMO

BACKGROUND: The combination of resistance training (RT) and aerobic training is believed to achieve the best effects. Several different aerobic training methods have emerged in combination with or as a substitute for traditional RT. This study wished to verify which RT is safest in terms of injury prevalence and incidence. Also, it ascertained the characteristics of the injured subjects, the level of severity of the injuries and what definitions of injuries the available studies use. METHODS: This systematic review followed the PRISMA recommendations and was registered in PROSPERO with the number CRD42021257010. The searches were performed in the PubMed, Cochrane and Web of Science, electronic databases using the Medical Subject Headings terms "Resistance training" or "Strength training" or "Crossfit" or "Weightlifting" or "Powerlifting" combined (AND) with "Injury" or "Injuries" or "Sprain" AND "Incidence" or "Prevalence" AND "Epidemiology" or "Epidemiological" in the title or abstract. The last search was performed on March 2023. To be included in the review, the studies had to be available as full text, be clinical trials focusing on epidemiological injuries of resistance training. There was no time limit for the selection of articles. To assess the quality of the studies, the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) was used. RESULTS: The initial literature search resulted in 4982 studies. After reading the titles, abstracts and full text, 28 articles were selected for data extraction. Seventeen investigated the injuries in HIFT/CrossFit, three in powerlifting, three in strength training, three in weightlifting and one in strongman. In addition, one study examined the HIFT/CrossFit and weightlifting. The incidence of injuries presented in the studies ranged from 0.21/1000 h to 18.9/1000 h and the prevalence of injuries was 10% to 82%. In the quality assessment for STROBE, five studies were classified at level A, 21 at level B and two at level C. CONCLUSION: This systematic review showed that traditional strength training is the safest RT method, and strongman is the least safe regarding injuries. Few studies have been rated highly according to STROBE. Furthermore, few studies have been published on some RT methods. These two factors make it difficult to generalize the results.

Assuntos

Treinamento Resistido , Esportes , Entorses e Distensões , Humanos , Treinamento Resistido/métodos , Exercício Físico , Incidência

RESUMO

BACKGROUND: High intensity functional training (HIFT), usually called CrossFit, is a physical training that has gained much popularity in the past few years. The risk of acute and overuse injuries in HIFT is unclear. This study evaluated the incidence of injuries in HIFT, characterizing severity, location, and associated risk factors. METHODS: This cross-sectional study was conducted between January and May 2021. HIFT practitioners were recruited through social media and answered an online questionnaire on training characteristics and injury history. RESULTS: A total of 606 subjects (264 male and 342 female) were included. The average age of the participants was 29.78 ± 7.14 years. The mean height was 169.60 ± 8.96 cm, and the mean body mass was 73.69 ± 13.11 kg. Overall, participants were involved in HIFT for an average of 25.36 ± 20.29 months. A total of 58.6% of participants took part in 5 to 6 training sessions per week, 31.7% practiced 5 to 6 h per week. 62.7% of the responders performed other physical activities in parallel, 98.2% performed warm-up before the training, and a formal cooldown was accomplished by 29.4% of participants. 6.8% of athletes followed individual worksheets. 45.9% of participants participated in competition. CONCLUSIONS: The overall rate of injuries was 3.51/1000 h. 59.2% of subjects experienced two or more injuries. The shoulder was involved in 21.3% of cases, lower back in 18.3%, and the knee in 13.4%. No difference was found in injury rate between males and females. Experienced athletes were more prone to injury compared to those who trained under 12 months. Approximately the half of injuries did not cause training interruption. No difference was found in injury rate between males and females. The purpose of the participant did not impact the injury rate, nor did the practice of warm-up and cooldown, the time of weekly training, the league and level of competition. Finally, the participation in other sports in parallel did not demonstrated association with the injury occurrence. TRIAL REGISTRATION: The present study was approved by the Ethics and Research Committee by Plataforma Brazil and follows the Resolution 466/2012/CNS/MS/CONEP.

Assuntos

Traumatismos em Atletas , Transtornos Traumáticos Cumulativos , Treinamento Intervalado de Alta Intensidade , Esportes , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Brasil/epidemiologia , Estudos Transversais , Transtornos Traumáticos Cumulativos/epidemiologia , Traumatismos em Atletas/epidemiologia , Traumatismos em Atletas/terapia

RESUMO

The establishment of fatigue following the acute exercise stimulus is a complex and multi-factorial process, that might arise due to a range of distinct physiological mechanisms. However, a practical method of assessing CrossFit® athletes' recovery status has been neglected entirely in real-world sporting practice. The study describes the acute and delayed time course of recovery following the CrossFit® Benchmark Workout Karen. Eight trained men (28.4 ± 6.4 years; 1RM back squat 139.1 ± 26.0 kg) undertook the Karen protocol. The protocol consists of 150 Wall Balls (9 kg), aiming to hit a target 3 m high. Countermovement jump height (CMJ), creatine kinase (CK), and perceived recovery status scale (PRS) (general, lower and upper limbs) were assessed pre, post-0h, 24, 48 and 72 h after the session. The creatine kinase concentration 24 h after was higher than pre-exercise (338.4 U/L vs. 143.3 U/L; p = 0.040). At 48h and 72 h following exercise, CK concentration had returned to baseline levels (p > 0.05). The general, lower and upper limbs PRS scores were lower in the 24-h post-exercise compared to pre-exercise (general PRS: 4.7 ± 1.5 and 7.7 ± 1.7; p = 0.013; upper limbs PRS: 6.6 ± 1.3 and 7.5 ± 1.3; p = 0.037; lower limbs PRS: 3.9 ± 2.5 and 7.3 ± 0.1; p = 0.046). Our findings provide insights into the fatigue profile and recovery in acute CrossFit® and can be useful to coaches and practitioners when planning training programs. Moreover, recovery status can be useful to optimize training monitoring and to minimize the potential detrimental effects associated with the performance of repeated high-intensity sessions of CrossFit®.

RESUMO

Acute psychological responses to physical activity may help explain long-term adherence to it. Thus, we compared acute psychological responses to different exercise protocols with identical durations. Eighteen moderately active young adults [Mage = 23, SD = 3 years; MVO2max (maximum oxygen consumption) = 42.8, SD = 4.3 mL·kg-1·min-1; MBMI (body mass index) = 24, SD = 2 kg·m-2] completed three low-volume exercise sessions in a crossover research design: (a) sprint interval training (SIT), (b) burpee interval training (BIT) requiring 10 × 5 second efforts with 35 seconds of passive recovery, and (c) a single bout of vigorous intensity continuous training (VICT) requiring 6 minutes and 5 seconds of running at ∼85% of peak heart rate (HRpeak). We assessed participants' ratings of perceived exertion (RPE), affective valence, enjoyment, intention, preference, and self-reported recovery and wellness before, during, and after each session. BIT was associated with significantly greater enjoyment, preference, and exercise intention (at 5 × week) than VICT (p ≤ .05). SIT elicited greater RPE (M = 5.38, SD = 2.00) than both BIT (M = 2.88, SD = 1.23) and VICT (M = 3.55, SD = 1.38) (p ≤ .05), and we observed a higher increase in RPE over time with SIT versus BIT (p = .019). For affective valence, SIT (M = 0.55, SD = 2.12) elicited a more aversive response than both BIT (M = 2.55, SD = 1.09) and VICT (M = 1.94, SD = 1.51) (p ≤ .05), and there was a higher increase in this aversive response to SIT over time (p < .05). Forty-eight-hour postexercise session muscle soreness was significantly lower with VICT than with BIT (p = .03). Overall, BIT was associated with more positive psychological responses than SIT and VICT.

Assuntos

Treinamento Intervalado de Alta Intensidade , Corrida , Adulto , Exercício Físico/fisiologia , Treinamento Intervalado de Alta Intensidade/métodos , Humanos , Consumo de Oxigênio/fisiologia , Prazer , Adulto Jovem

RESUMO

BACKGROUND: To investigate the time-course effects of a self-regulated training session (performed at an rating perceived exertion of 6/10), all-out session, and a control session on the metabolic, hormonal, and brain derived neurotrophic factor (BDNF) responses in Functional-Fitness (FFT) participants. METHODS: In a randomized, crossover fashion, eight healthy males (age 28.1 ± 5.4 years old; body mass 77.2 ± 4.4 kg; VO2max: 52.6 ± 4.6 mL.(kg.min)-1; 2000 m rowing test 7.35 ± 0.18 min; 1RM back squat 135.6 ± 21.9 kg) performed a FFT session under two different conditions: all-out, or with the intensity controlled to elicit an rating perceived exertion (RPE) of 6 in the Borg 10-point scale (RPE6). A control session (no exercise) was also completed. Metabolic (lactate and creatine kinase), hormonal (testosterone and cortisol), and BDNF responses were assessed pre, post-0 h, 1 h, 2 h and 24 h after the sessions. RESULTS: Creatine kinase concentrations were significantly higher (p ≤ 0.05) after 24 h for both training sessions. Total and free testosterone concentrations were lower post-2 h for all-out when compared to the RPE6 session (p ≤ 0.05). Serum cortisol concentration increased post-0 h (p = 0.011) for RPE6 and post-0 h (p = 0.003) and post-1 h (p = 0.030) for all-out session when comparing to baseline concentrations. BDNF was significantly higher (p = 0.002) post-0 h only for the all-out session when compared to baseline. A positive correlation between blood lactate concentrations and BDNF (r = 0.51; p = 0.01) was found for both effort interventions. CONCLUSIONS: A single FFT session when performed in all-out format acutely increases the concentrations of serum BDNF. However, physiological stress markers show that the all-out session requires a longer recovery period when compared to the RPE6 protocol. These findings can be helpful to coaches and practitioners design FFT session.

RESUMO

OBJECTIVE: Verify the incidence and rate of joint and muscle injuries with the practice of CrossFit® and the potential risk factors for injuries in men and women. METHODS: A total of 184 CrossFit® participants (97 men and 87 women). A questionnaire was conducted based on characterization, training routine, injuries, and additional information. The incidence refers to the number of new cases of injury in the sample during the CrossFit® training. The injury rate was calculated by estimating the number of weekly training hours and converted into the number of injuries per 1000 training hours. RESULTS: Among the participants, 38.6% reported some type of injury, being joint injuries (83.1%) and/or muscle injuries (45.1%). The injury rate was 3.4/1000 h, with men having a higher rate. The location of the joint injuries was shoulders, wrists, and elbows, in addition to the lumbar spine in women. As for muscle injuries, the deltoid, upper back muscles, and quadriceps femoris were the most reported in men and deltoid, trapezius, upper back muscles, and gastrocnemius in women. CONCLUSIONS: A better understanding of the anatomical distribution of the injuries may help coaches prescribe the most adequate workout that may reduce the likelihood of injuries occurring in CrossFit® training participants. It was demonstrated that gender, experience, weekly frequency, and previous injuries are important factors, and professionals must be concerned with the assessment of the participants and with an individualized progression in order to avoid risks.

Assuntos

Traumatismos em Atletas , Sistema Musculoesquelético , Traumatismos em Atletas/epidemiologia , Traumatismos em Atletas/etiologia , Feminino , Humanos , Incidência , Masculino , Músculos/lesões , Sistema Musculoesquelético/lesões , Fatores de Risco

RESUMO

The purpose of the present study was to compare the heart rate (HR), blood lactate and training load between different CrossFit® workouts, with equalized total work volumes in men and women. The study included 23 individuals (13 men and 10 women) experienced in CrossFit® training, who performed two workouts with different training types (as many reps as possible (AMRAP) and 'for time') but an equalized volume. Measurements of lactate, HR and rating of perceived exertion (RPE) were performed. The results show that there was no HR interaction between workout time and sex (p = 0.822; η2 = 0.006) and between workout type and sex (p = 0.064, η2 = 0.803). The HR significantly differed during each workout type (p < 0.001, η2 = 0.621), but not between the two workout types (p = 0.552, η2 = 0.017). Lactate showed no difference between the workout types (p = 0.474, η2 = 0.768), although the training load was higher (p = 0.033, η2 = 0.199) in women when they performed AMRAP. Altogether, the HR was not significantly different between training types or sex, while RPE, lactate and training load showed statistically significant differences depending on the group (women or men) or workout type (AMRAP or 'for time').

RESUMO

Background: CrossFit® training is a high-intensity functional training program that aims to increase physical functional performance through biochemical responses, i.e., hormonal, metabolic, and inflammatory responses. Most hormonal, metabolic, and inflammatory changes induced by CrossFit® training have been reported in isolated clinical studies. The purpose of this review was to systematically explore the existing literature on characterization of hormonal, metabolic, and inflammatory responses resulting from CrossFit® training. Methods: A systematic search of the literature was conducted in PubMed, Web of Science and Scopus from August 2019 to October 2019. Studies were selected through critical review of the content. Using specific keywords, 623 articles were found, of which 597 were excluded for ineligibility, and 25 were eligible. The papers were separated according to subject area: hormonal (n = 8), metabolic (n = 19), and inflammatory (n = 6) changes. All were published between 2015 and 2019. Results: This review reveals potential effects of CrossFit® training on hormonal, metabolic, and inflammatory responses. However, studies had low levels of evidence and reliability due to methodological limitations. Conclusion: In summary, the results showed a greater volume and intensity of workouts accentuate the responses, that are of paramount importance for improving understanding of the effects of CrossFit® training and serve as a basis for prescribing future exercise protocols.

RESUMO

Abstract Aim: To verify the acute effect of sodium bicarbonate (NaHCO3) supplementation on performance during CrossFit® workout. Methods: Nine experienced males (30.8 ± 3.5 years; 84.4 ± 9.5 kg; 177.5 ± 4.03 cm; 2.2 ± 1.0 years) in CrossFit® participated in this study. They were allocated to two conditions: a) supplementation with 0.3 g.kg-1 of body weight of NaHCO3 and b) supplementation with 0.045 g.kg-1 of body weight of sodium chloride (NaCl). Blood lactate was analyzed at two different moments: before (lac-pre) and after the training protocol (lac-post). The heart rate (HR) and the rating of perceived exertion (RPE) were also collected every two minutes during the execution of the training protocol, and the RPE was also collected after it was finished. At the end of the training protocol, a questionnaire to measure gastrointestinal side effects (GSE) was answered by the participants. Repetitions performed in the training protocol was computed to evaluate the performance during the workout. Results: The results showed that there were no differences found when comparing the conditions for all parameters. HR and RPE were different in the first few minutes (< 4-6 minutes) when compared to the final minutes (> 14 minutes) of the workout. The area under the curve of HR and RPE was significantly lower in the NaHCO3 condition. Conclusion: Acute NaHCO3 supplementation did not improve performance during workout 'Cindy' in experienced men. Supplementation also did not alter hemodynamic and perceptual parameters, nor did it cause any GSE. However, responses as a function of time were reduced with NaHCO3 supplementation.

Assuntos

Humanos , Exercício Físico/fisiologia , Bicarbonato de Sódio/administração & dosagem , Fadiga Muscular/fisiologia , Ácido Láctico/sangue , Inquéritos e Questionários

RESUMO

Functional Fitness Training (FFT) programs are characterized by utilizing a high volume of training and using a variety of high intensity exercises. While FFT are growing in the number of practitioners and popularity, the relationship between physiological biomarkers and subjective scales in the specific context of FFT has not yet been evaluated in the literature. The purpose of the present study was to monitor the time-course response of cytokines (IL-10 and 1L-1ß), immune variables (C-reactive protein -CRP and immunoglobulin A-IgA), hormonal milieu (cortisol-C, total testosterone-TT, free testosterone-FT and testosterone/cortisol-T/C ratio), creatine kinase-CK, muscle performance (countermovement jump height) and perceived well-being (WB) following a functional fitness competition. Nine amateur male athletes (age 27.1 ± 4.1 years; training experience 2.2 ± 1.3 years) completed five workouts over three consecutive days of FFT-competition. All variables were measured before, 24 h, 48 h, and 72 h following the last day of competition. The FFT-competition induced a decrease in IL10/IL1ß ratio approximately 5% after 24h, 21% after 48h and 31% after 72h. Delta T/C ratio remained unchanged during the post-competition period. IgA displayed a significant increase 24h and 72h post FFT-competition. The WB status score was higher 72h after the FFT-competition as compared with pre-competition. The present findings suggest that FFT-competition induces transient changes in some inflammatory and hormonal biomarkers, and perceived well-being seems to be efficient to detect changes in muscle performance.

RESUMO

The purpose of this study was to assess whether the self-regulation of training intensity based on rating of perceived exertion (RPE) is a reliable method to control the intensity during metabolic conditioning sessions of functional fitness. In addition, the relationship between RPE and the changes in heart rate, number of repetitions, and lactate responses was also analyzed. Eight male participants (age 28.1 ± 5.4 years; body mass 77.2 ± 4.4 kg; VO2 max: 52.6 ± 4.6 mL·(kg·min)-1 completed two sessions (five to seven days apart), in a randomized order, under different conditions, as follows: (1) all-out (ALL), or (2) self-regulation of intensity based on an RPE of six (hard) on the Borg CR-10 scale (RPE6). The rating of perceived exertion, lactate (LAC), and heart rate (HR) response were measured before, during, and immediately after the sessions. The RPE and LAC during the all-out sessions were higher (p < 0.0005) than the RPE6 session for all of the analyzed time points during the session. There was no difference in the HR area under the curve for the all-out and RPE6 sessions. The average number of repetitions performed was lower (p ≤ 0.009) for the RPE6 session (190.5 ± 12.5 repetitions) when compared to the all-out session (214.4 ± 18.6 repetitions). There was a significant correlation between the RPE and LAC (p = 0.005; r = 0.66; large) and number of repetitions during the session (p = 0.026; r = 0.55; large). No correlation was observed between the RPE and HR (p = 0.147; r = 0.380). These results indicate that the self-regulation of intensity of effort based on the RPE may be a useful tool to control the exercise intensity during a metabolic conditioning session of functional fitness.

RESUMO

The aim of this case study was to quantify the magnitude of internal load, acute/chronic workload ratio (ACWR), well-being perception, and heart rate variability (HRV) following 38 weeks of functional-fitness training in a female elite athlete. The internal load was obtained with session rating perceived exertion (session-RPE) while the ACWR was calculated by dividing the acute workload by the chronic workload (four-week average). Furthermore, HRV measurements were analyzed via a commercially available smartphone (HRV4training) each morning upon waking whilst in a supine position. The magnitude of internal load was: the weekly mean total during the 38 weeks was 2092 ± 861 arbitrary units (AU); during the preparation for the Open 2018 was 1973 ± 711 AU; during the Open 2018 it was 1686 ± 412 AU; and during the preparation for the Regionals was 3174 ± 595 AU. The mean ACWR was 1.1 ± 0.5 and 50% of the weeks were outside of the 'safe zone'. The well-being during the 38 weeks of training was 19.4 ± 2.3 points. There were no correlations between training load variables (weekly training load, monotony, ACWR, and HRV), and recuperation subjective variables (well-being, fatigue, sleep, pain, stress, and mood). This case study showed that the training load can be varied in accordance with preparation for a specific competition and ACWR revealed that 50% of the training weeks were outside of the 'safe zone', however, no injuries were reported by the athlete. The effectiveness and cost of these methods are very practical during real world functional-fitness.

RESUMO

The metabolic and hormonal consequences of high-intensity functional training regimens such as CrossFit® (CF) are unclear. Little is known about the triggers and clinical and biochemical features of CF-related overtraining syndrome (OTS). The EROS study compared endocrine and metabolic responses, and eating, social, psychological and body characteristics of OTS-affected (OTS) and healthy athletes (ATL), and non-physically active controls (NPAC). The current study is a post-hoc analysis of the CF subgroups of the EROS study, to evaluate specific characteristics of CF in ATL and OTS. Parameters were overall and pairwise compared among OTS-affected (CF-OTS) and healthy (CF-ATL) athletes that exclusively practiced CF, and NPAC. CF-ATL yielded earlier and enhanced cortisol, GH, and prolactin responses to an insulin tolerance test (ITT), increased neutrophils, lower lactate, increased testosterone, improved sleep quality, better psychological performance, increased measured-to-predicted basal metabolic rate (BMR) ratio and fat oxidation, and better hydration, when compared to NPAC. Conversely, more than 90% of the adaptive changes in CF were lost under OTS, including an attenuation of the hormonal responses to an ITT, increased estradiol, decreased testosterone, and decreased BMR and fat oxidation; the most remarkable trigger of OTS among "HIFT athletes" was the long-term low carbohydrate and calorie intake.

Assuntos

Transtornos Traumáticos Cumulativos/etiologia , Transtornos Traumáticos Cumulativos/metabolismo , Condicionamento Físico Humano/efeitos adversos , Condicionamento Físico Humano/métodos , Adolescente , Adulto , Afeto/fisiologia , Biomarcadores/metabolismo , Fenômenos Biomecânicos , Catecolaminas/urina , Transtornos Traumáticos Cumulativos/fisiopatologia , Técnicas de Diagnóstico Endócrino , Estradiol/sangue , Hormônio do Crescimento Humano/sangue , Humanos , Hidrocortisona/análise , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/fisiologia , Insulina/sangue , Ácido Láctico/sangue , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/fisiologia , Prolactina/sangue , Saliva/química , Sono/fisiologia , Testosterona/sangue , Adulto Jovem

RESUMO

Extreme conditioning programmes (ECPs, eg, CrossFit, Insanity and Gym Jones) are a growing fitness regimen characterised by functional movements performed at high-intensity and with constantly varying movements. While the popularity and number of practitioners of ECPs are growing, a debate has been established between what is observed in the scientific literature and anecdotal reports from athletes, coaches and physicians about safety (incidence and prevalence of injuries and rhabdomyolysis) and benefits (physical and mental health). In this article, we review the prevalence and incidence of injuries, rhabdomyolysis, physiological responses and chronic adaptations to ECPs. The majority of the available evidence confirm that the estimated injury rate among athletes participating in ECPs is similar to that in weightlifting and most other recreational activities. Additionally, ECP sessions resulted in increased acute oxidative, metabolic and cardiovascular stress, and depending on the stimulus (intensity, duration and non-usual exercise) and training status of the practitioner, an ECP session may precipitate rhabdomyolysis. In the scientific literature, the current chronic effects of ECPs showed little or no effects on body composition and improvements in physical fitness and psychological parameters; however, further studies are important.

RESUMO

BACKGROUND: CrossFit is recognized as one of the fastest growing high-intensity functional training modes in the world. However, scientific data regarding the practice of CrossFit is sparse. Therefore, the objective of this study is to analyze the findings of scientific literature related to CrossFit via systematic review and meta-analysis. METHODS: Systematic searches of the PubMed, Web of Science, Scopus, Bireme/MedLine, and SciELO online databases were conducted for articles reporting the effects of CrossFit training. The systematic review followed the PRISMA guidelines. The Oxford Levels of Evidence was used for all included articles, and only studies that investigated the effects of CrossFit as a training program were included in the meta-analysis. For the meta-analysis, effect sizes (ESs) with 95% confidence interval (CI) were calculated and heterogeneity was assessed using a random-effects model. RESULTS: Thirty-one articles were included in the systematic review and four were included in the meta-analysis. However, only two studies had a high level of evidence at low risk of bias. Scientific literature related to CrossFit has reported on body composition, psycho-physiological parameters, musculoskeletal injury risk, life and health aspects, and psycho-social behavior. In the meta-analysis, significant results were not found for any variables. CONCLUSIONS: The current scientific literature related to CrossFit has few studies with high level of evidence at low risk of bias. However, preliminary data has suggested that CrossFit practice is associated with higher levels of sense of community, satisfaction, and motivation.

RESUMO

The aim of this study was to analyze blood lactate concentration (LAC), heart rate (HR), and rating perceived exertion (RPE) during and after shorter and longer duration CrossFit® sessions. Nine men (27.7 ± 3.2 years; 11.3 ± 4.6% body fat percentage and training experience: 41.1 ± 19.6 months) randomly performed two CrossFit® sessions (shorter: ~4 min and longer: 17 min) with a 7-day interval between them. The response of LAC and HR were measured pre, during, immediately after, and 10, 20, and 30 min after the sessions. RPE was measured pre and immediately after sessions. Lactate levels were higher during the recovery of the shorter session as compared with the longer session (shorter: 15.9 ± 2.2 mmol/L/min, longer: 12.6 ± 2.6 mmol/L/min; p = 0.019). There were no significant differences between protocols on HR during (shorter: 176 ± 6 bpm or 91 ± 4% HRmax, longer: 174 ± 3 bpm or 90 ± 3% HRmax, p = 0.387). The LAC was significantly higher throughout the recovery period for both training sessions as compared to pre-exercise. The RPE was increased immediately after both sessions as compared to pre-exercise, while there was no significant difference between them (shorter: 8.7 ± 0.9, longer: 9.6 ± 0.5; p = 0.360). These results demonstrated that both shorter and longer sessions induced elevated cardiovascular responses which met the recommendations for gains in cardiovascular fitness. In addition, both training sessions had a high metabolic and perceptual response, which may not be suitable if performed on consecutive days.