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Background: Upper-body exercise is increasingly applied in athletic and exercise settings; however, acute physiological and perceptual differences compared to lower-body exercise remain insufficiently characterized. This study compared maximal performance parameters during incremental upper- and lower-body exercise in healthy adults. Methods: Seventeen moderately trained participants (eight females, nine males) completed randomized incremental tests on a hand crank ergometer (HCE) and a cycle ergometer (CE). Maximal fat oxidation (MFO), intensity at maximal fat oxidation (FAT_max), peak oxygen uptake (VO₂^peak), maximal heart rate (HR_peak), peak power output (PPO), immediate post-exercise lactate (LA_post), and differentiated ratings of perceived exertion (RPE_breathing and RPE_muscles) were assessed. Results: MFO was significantly lower during HCE compared with CE (0.26 vs. 0.55 g·min⁻¹, p < 0.001), occurring at a lower FAT_max (42.6% vs. 51.6% of VO₂^peak_, p = 0.016). Furthermore, relative VO₂^peak (34.1 vs. 48.9 mL·kg⁻¹·min⁻¹, p < 0.001), HR_peak (178 vs. 189 beats·min⁻¹, p < 0.001), and relative PPO (1.8 vs. 4.1 W·kg⁻¹, p < 0.001) were substantially reduced during HCE. While RPE_breathing was higher during CE (19.1 vs. 17.6, p < 0.001), RPE_muscles (19.4 vs. 19.8, p = 0.111) and LA_post (9.8 vs. 8.6 mmol·L⁻¹, p = 0.060) did not differ significantly between modalities. No significant modality-by-sex interactions were observed for any outcome. Conclusions: These findings demonstrate pronounced modality-specific differences in metabolic, cardiorespiratory, and perceptual responses. Exercise modality should therefore be carefully considered when interpreting maximal exercise tests and prescribing training or rehabilitation programs.

To avoid potentially dangerous slips during alpine activities like hiking, soles of outdoor shoes are supposed to provide grip on natural outdoor surfaces with varying characteristics. The aim of the study was to investigate how six commercially available soles perform on three different alpine surfaces and how parameters that are known to be linked to friction outcomes are associated with the static coefficient of friction ( µ _s ). In addition, the effect of different gait phases from heel-strike to toe-off phase were considered. The µ _s of outdoor shoe soles were determined at constant temperature in a linear tribometer on ice, snow and granite. The parameters hardness, contact pressure and roughness of the soles were determined to explore their potential relationships with µ _s outcomes. To simulate the different phases of human gait, six angles from 10° heel-strike, stance-phase and 5°, 11°, 22°, 28° toe-off phase were analyzed. The tested soles performed significantly different on ice and granite, but not on snow, which was expected due to known hysteresis and adhesion mechanisms. All tested parameters appeared to be associated with friction, showing relationships. However, the associations shown in the correlation coefficient varied between the tested surfaces. Moreover, interaction effects of soles and angles could be observed. The measured angles indicated an alteration of friction performance, with respect to the phase of gait. In dependence of the intended purpose of a shoe sole, material characteristics and geometry should be considered when manufacturing outdoor soles to increase the friction on different surfaces.

Background: Foam rolling has become an increasingly popular self-myofascial release (SMR) technique among athletes to prevent injuries, improve recovery, and increase athletic performance. This study investigated how SMR improves mechanical and movement efficiency in recreational road cyclists. Methods: We conducted an exploratory randomized controlled trial (RCT) to investigate the effects of SMR using a foam roller on biomechanical and physiological performance parameters over a six-month period. A total of 32 male participants, aged 26–57 years, with a mean Body Mass Index (BMI) of 24.0 kg/m² (SD = 2.2), were randomly assigned to either an intervention group (n = 16), which incorporated a standardized SMR program into their post-exercise recovery, or a control group (n = 16), which followed the same cycling protocol without SMR. The training program included heart rate-controlled strength endurance intervals. As the primary target, the variables we investigated included torque effectiveness, leg force symmetry, and pedal smoothness. Secondary measurements included submaximal oxygen uptake (VO₂) as well as bioelectrical variables, which we analyzed using classic, repeated-measures ANOVA models and descriptive statistical methods. Results: The analysis revealed significant interaction effects in favor of the intervention group for torque effectiveness (η²_p = 0.434), leg strength symmetry (η²_p = 0.303), and pedal smoothness (η²_p = 0.993). No significant group × time interactions were found for submaximal VO₂ or bioelectrical parameters. Conclusions: Our findings indicate that foam rolling may serve as an effective adjunct to endurance training by enhancing functional neuromuscular performance in cyclists, particularly in torque control and pedal coordination. Its impact on aerobic efficiency and muscle composition appears to be minimal. The results support theoretical models that attribute SMR benefits to proprioceptive, circulatory, and neuromuscular mechanisms rather than structural tissue adaptations.