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Objectives: Increased cardiorespiratory responses and changes in muscle activity and running kinematics occur in running after cycling compared with isolated running. Nevertheless, little is known about the causes of these changes. Cycling exercise decreases the stretch-shortening cycle (SSC) function, which can influence subsequent running. This study aimed to clarify whether the decrease in SSC function after cycling causes cardiorespiratory and biomechanical changes in subsequent running.Design: Cross-sectional laboratory study. Participants were divided into two groups based on SSC function: an SSC dec group (those with decreased SSC function after cycling) and an SSC non-dec group (those without decreased SSC function after cycling).Methods: Eighteen participants (10 triathletes and 8 runners) completed maximal aerobic tests for running and cycling. After these sessions, a submaximal run-cycle-run test was performed to compare between control run (no preceding cycle) and transition run (preceded by cycling). A jump test was administered before and after the submaximal cycling. SSC function was calculated as the ratio of the jump height to the time spent in contact with the ground (reactive strength index). Gas exchange measures, heart rate, and gait parameters were collected throughout the test.Results: Oxygen uptake and ventilation were increased by cycling in the SSC dec group but not in the SSC non-dec group. In both groups, there were no significant differences in the gait parameters between control and transition runs.Conclusions: The decrease in SSC function after cycling would increase cardiorespiratory responses in subsequent running. [ABSTRACT FROM AUTHOR]

• Biogeochemical characteristics for the Antarctic brash ice were examined. • Brash ice was similar for biogeochemical components to those in ice core samples. • Icebergs were evaluated as end-member values for meteoric water origin. We analyzed biogeochemical components of brash ice, originating from sea ice and icebergs, collected in the Indian sector of the Southern Ocean during the summer and autumn of 2018–2020. Ice samples, collected from seawater by net or cage methods, were melted in the dark under cool conditions to measure physical and biogeochemical components such as salinity, stable oxygen isotopes, nutrients, and chlorophyll-a. We compared brash ice parameters with those of seawater samples from the temperature minimum layer, corresponding to the water in which the sea ice originated, to examine the effects of processes such as brine drainage, snow-ice formation, and biological activities on the biogeochemical components in sea ice. Samples from icebergs (ice formed on land) had salinity of zero and low concentrations of all other components, suggesting that the atmospheric deposition of nutrients is minimal in this clean environment. However, sea ice samples had a wide range of values for each parameter. Our results show that meteoric water makes a smaller contribution to sea ice than it typically does to multi-year landfast ice, and there is no correlation between this meteoric water contribution and nutrient concentrations, which suggests that the contribution of snow-ice formation to nutrients within sea ice is subordinate to the role of biological processes. Nutrient and chlorophyll-a concentrations in our brash ice samples are of similar magnitude to those in sea ice samples collected in the same area by coring of thick pack ice. Our data represent end-member values that may be useful to estimate the respective contributions of snow, sea ice, and seawater to surface water samples. [ABSTRACT FROM AUTHOR]