ABSTRACT
Purpose: Lactate threshold (LT) is a critical performance measure traditionally obtained using costly laboratory-based tests. Wearables offer a practical and noninvasive alternative for LT assessment in recreational and professional athletes. However, the comparability of these estimates with the regular field tests requires further evaluation. Patients and Methods: In our sample of 26 participants (nf=7 and nm=19), we compared the estimated running pace and heart rate (HR) at LT with two subsequent tests. First, participants performed the Fenix 7® threshold running test after a calibration phase. Subsequently, they were tested in a standardized, graded blood lactate field test. Age was 25.97 (± 6.26) years, and body mass index (BMI) was 24.58 (± 2.8) kg/m2. Results: Pace at LT calculated by Fenix 7® (M=11.87 km/h ± 1.26 km/h) was 11.96% lower compared to the field test (M=13.28 km/h ± 1.72 km/h), which was significant (p <0.001, d=-1.19). HR estimated by the Fenix 7® at LT was 1.71% lower (p >0.05). LT data obtained in the field test showed greater overall variance. Conclusion: Our results suggest sufficient accuracy of Fenix 7® LT estimates for recreational athletes. It can be assumed that for professional athletes, it would fail to provide the nuanced data needed for high-quality training management.
ABSTRACT
The functional fitness training program CrossFit® is experiencing fast-growing and widespread popularity with day-to-day varying 'Workouts of the Day' (WOD). Even among tactical athletes, the training program is widely applied. Nevertheless, there is a lack of data on which parameters influence CrossFit® performance. For this reason, the purpose of this study is to conduct a systematic review of the existing literature to identify and summarize predictors of CrossFit® performance and performance enhancement. In accordance with the PRISMA guidelines, a systematic search of the following databases was conducted in April 2022: PubMed, SPORTDiscus, Scopus, and Web of Science. Using the keyword 'CrossFit', 1264 entries are found, and 21 articles are included based on the eligibility criteria. In summary, the studies show conflicting results, and no specific key parameter was found that predicts CrossFit® performance regardless of the type of WOD. In detail, the findings indicate that physiological parameters (in particular, body composition) and high-level competitive experience have a more consistent influence than specific performance variables. Nevertheless, in one-third of the studies, high total body strength (i.e., CrossFit® Total performance) and trunk strength (i.e., back squat performance) correlate with higher workout scores. For the first time, this review presents a summary of performance determinants in CrossFit®. From this, a guiding principle for training strategies may be derived, suggesting that a focus on body composition, body strength, and competition experience may be recommended for CrossFit® performance prediction and performance enhancement.
ABSTRACT
CrossFit® is a functional fitness training program known for its day-to-day varying "Workouts of the Day" (WOD). In accordance with the 'CrossFit® Level 1 Training Guide', regular CrossFit® training sessions consist of Warm-up, Mobility, Skill/Power training, WOD, and Cool-down. Despite the fast-growing and widespread popularity, data on the practical implementation of the training program based on scientific evidence are rare. Therefore, the purpose of this study is to systematically review the existing literature on the physiological effects of regular CrossFit® training in full extent instead of stand-alone WODs and to examine the impact of the COVID-19 pandemic on the training behavior of CrossFit® athletes. A systematic search was conducted following the PRISMA guidelines in April 2022 and updated in July 2022 using the following databases: PubMed, SPORTDiscus, Scopus, and Web of Science. Using the keyword "CrossFit", 1,264 records were found. Based on the eligibility criteria, 12 studies are included and separated by topics: acute-short term physiological response (n = 8), and impact of the COVID-19 pandemic (n = 4). The results show that studies of regular training sessions were rarely conducted and contradicted the existing knowledge of the physiological demands [e.g., heart rate (HR)] of CrossFit®. In detail, included studies demonstrate that training sessions last 30-60 min and provide a progressive increase in cardiovascular load up to maximal effort activity (>90% HRmax), differing from stand-alone WODs exclusively at high-intensity. Also, scarce research exists on COVID-19-pandemic-induced effects on training behavior, and studies are of moderate to low quality. There is still a lack of comprehensive analyses on the acute physiological effects of regular training sessions and the consequences of the COVID-19 pandemic in the scientific literature. Moreover, the inconsistent terminology used in CrossFit® research complicates generalized conclusions. Therefore, future research on the training methodology of CrossFit® needs to overcome terminological inequalities and examine scientifically the implementation of the concept by considering regular training sessions under practical settings.
