A modified formula using energy system contributions to calculate pure maximal rate of lactate accumulation during a maximal sprint cycling test

V ˙ Lamax: determining the optimal test duration for maximal lactate formation rate during all-out sprint cycle ergometry

PURPOSE

This study aimed to ascertain the optimal test duration to elicit the highest maximal lactate formation rate ( V ˙ Lamax), whilst exploring the underpinning energetics, and identifying the optimal blood lactate sampling period.

METHODS

Fifteen trained to well-trained males (age 27 ± 6 years; peak power: 1134 ± 174 W) participated in a randomised cross-over design completing three all-out sprint cycling tests of differing test durations (10, 15, and 30 s). Peak and mean power output (W and W.kg-1), oxygen uptake, and blood lactate concentrations were measured. V ˙ Lamax and energetic contributions (phosphagen, glycolytic, and oxidative) were determined using these parameters.

RESULTS

The shortest test duration of 10 s elicited a significantly (p = 0.003; p < 0.001) higher V ˙ Lamax (0.86 ± 0.17 mmol.L-1.s-1; 95% CI 0.802-0.974) compared with both 15 s (0.68 ± 0.18 mmol.L-1.s-1; 95% CI 0.596-0.794) and 30 s (0.45 ± 0.07 mmol.L-1.s-1; 95% CI 0.410-0.487). Differences in V ˙ Lamax were associated with large effect sizes (d = 1.07, d = 3.15). We observed 81% of the PCr and 53% of the glycolytic work completed over the 30 s sprint duration was attained after 10 s. BLamaxpost were achieved at 5 ± 2 min (ttest 10 s), 6 ± 2 min (ttest 15 s), and 7 ± 2 min (ttest 30 s), respectively.

CONCLUSION

Our findings demonstrated a 10 s test duration elicited the highest V ˙ Lamax. Furthermore, the 10 s test duration mitigated the influence of the oxidative metabolism during all-out cycling. The optimal sample time to determine peak blood lactate concentration following 10 s was 5 ± 2 min.

Advancing athletic assessment by integrating conventional methods with cutting-edge biomedical technologies for comprehensive performance, wellness, and longevity insights

In modern athlete assessment, the integration of conventional biochemical and ergophysiologic monitoring with innovative methods like telomere analysis, genotyping/phenotypic profiling, and metabolomics has the potential to offer a comprehensive understanding of athletes' performance and potential longevity. Telomeres provide insights into cellular functioning, aging, and adaptation and elucidate the effects of training on cellular health. Genotype/phenotype analysis explores genetic variations associated with athletic performance, injury predisposition, and recovery needs, enabling personalization of training plans and interventions. Metabolomics especially focusing on low-molecular weight metabolites, reveal metabolic pathways and responses to exercise. Biochemical tests assess key biomarkers related to energy metabolism, inflammation, and recovery. Essential elements depict the micronutrient status of the individual, which is critical for optimal performance. Echocardiography provides detailed monitoring of cardiac structure and function, while burnout testing evaluates psychological stress, fatigue, and readiness for optimal performance. By integrating this scientific testing battery, a multidimensional understanding of athlete health status can be achieved, leading to personalized interventions in training, nutrition, supplementation, injury prevention, and mental wellness support. This scientifically rigorous approach hereby presented holds significant potential for improving athletic performance and longevity through evidence-based, individualized interventions, contributing to advances in the field of sports performance optimization.

Applied high-intensity interval cardio yoga improves cardiometabolic fitness, energetic contributions, and metabolic flexibility in healthy adults

Purpose: Currently, there is no interventional approach to increase the intensity of Surya Namaskar a popular hatha yoga sequence used worldwide. Therefore, this study investigated how tempo-based high-intensity interval cardio yoga (HIICY) and traditional interval hatha yoga (TIHY) affects cardiometabolic fitness in active adults. Methods: Twenty physically active male and female individuals were randomly separated into HIICY (5 males, 5 females, 1.5 s tempo) and TIHY (5 males, 5 females, 3 s tempo) groups. The intervention included twelve exercise sessions for 4 weeks in both groups. Participants conducted a ramp test to determine their maximal oxygen uptake (V ˙ O2max), maximal velocity at V ˙ O2max (vV ˙ O2max), and maximal heart rate (HRmax). Afterward, they performed a 10-min high-intensity cardio yoga test (HICYT) to determine heart rate (HRpeak and HRmean), oxygen uptake (V ˙ O2peak and V ˙ O2mean), respiratory exchange ratio (RER), blood lactate concentrations (La- peak and ∆La-), fat and carbohydrate oxidations (FATox, CHOox), and energetic contributions (oxidative; W Oxi, glycolytic; W Gly, and phosphagen; W PCr, total energy demand; W Total). Results: V ˙ O2max and vV ˙ O2max showed time and group × time interactions (p < 0.01, p < 0.0001, p < 0.001, respectively). V ˙ O2max after HIICY was significantly higher than in pre-testing and following TIHY (p < 0.001, p < 0.0001, respectively). V ˙ O2peak, V ˙ O2mean, RER, HRpeak, and HRmean during the 10-min HICYT showed significant time effects (p < 0.05). ∆La- indicated a group × time interaction (p < 0.05). Group x time interaction effects for FATox at the fourth and sixth minute were observed (p < 0.05, respectively). Absolute (kJ) and relative (%) W Oxi, W Gly, and W Total showed time and group × time interaction effects (p < 0.05, p < 0.01, respectively). Furthermore, %W Gly was reduced following HIICY (p < 0.05). Additionally, V ˙ O2max and vV ˙ O2max were highly correlated with W Oxi in kJ (r = 0.91, 0.80, respectively). Moderate to high correlations were observed among CHOox, FATox, and absolute V ˙ O2max (r = 0.76, 0.62, respectively). Conclusion: A 4-week period of HIICY improved cardiometabolic fitness, oxidative capacity, and metabolic flexibility compared with TIHY, in physically active adults. Therefore, HIICY is suitable as HY-specific HIIT and time-efficient approach for relatively healthy individuals.