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Objective: To determine if 35 days of creatine supplementation (Cr) followed by 28 days of no supplementation altered lower leg anterior compartment pressure (ACP) at rest and after exercise.Design and Setting: Subjects were divided into 2 treatment groups: (1) high dose (0.3 g Cr x kg body mass[-1] x d[-1] for 7 days followed by 0.03 g Cr x kg body mass[-1] x d[-1] for 28 days), or (2) low dose (0.03 g Cr x kg body mass[-1] x d[-1] for 35 days). After 35 days, supplementation was terminated, and no Cr was ingested for 28 days.Subjects: Sixteen physically active, healthy, college-aged males (VO2max = 47.6 +/- 5.1 mL x kg[-l x min[-1]).Measurements: At baseline, 7 days and 35 days of supplementation, and 28 days postsupplementation, ACP was measured preexercise and immediately, 1, 5, 10, and 15 minutes postexercise after a treadmill run at 80% VO2max.Results: For ACP, there was no significant group-by-time interaction, but there was a significant time effect for group when the data were combined. ACP was significantly increased at preexercise, immediately postexercise, and 1, 5, and 10 minutes from baseline to 7 days. ACP remained significantly elevated from baseline at 35 days immediately postexercise and 1 minute postexercise. After 28 days of no supplementation, ACP began to return to presupplementation levels, with only the 1-minute postexercise measurement significantly elevated from baseline.Conclusions: Creatine supplementation increased ACP at rest and after exercise, and ACP began to return to normal after 28 days of no supplementation. [ABSTRACT FROM AUTHOR]

Conspecific density dependence (CDD) in plant populations is widespread, most likely caused by local-scale biotic interactions, and has potentially important implications for biodiversity, community composition, and ecosystem processes. However, progress in this important area of ecology has been hindered by differing viewpoints on CDD across subfields in ecology, lack of synthesis across CDD-related frameworks, and misunderstandings about how empirical measurements of local CDD fit within the context of broader ecological theories on community assembly and diversity maintenance. Here, we propose a conceptual synthesis of local-scale CDD and its causes, including species-specific antagonistic and mutualistic interactions. First, we compare and clarify different uses of CDD and related concepts across subfields within ecology. We suggest the use of local stabilizing/destabilizing CDD to refer to the scenario where local conspecific density effects are more negative/positive than heterospecific effects. Second, we discuss different mechanisms for local stabilizing and destabilizing CDD, how those mechanisms are interrelated, and how they cut across several fields of study within ecology. Third, we place local stabilizing/destabilizing CDD within the context of broader ecological theories and discuss implications and challenges related to scaling up the effects of local CDD on populations, communities, and metacommunities. The ultimate goal of this synthesis is to provide a conceptual roadmap for researchers studying local CDD and its implications for population and community dynamics., (© 2024 John Wiley & Sons Ltd.)

When plants die, neighbours escape competition. Living conspecifics could disproportionately benefit because they are freed from negative intraspecific processes; however, if the negative effects of past conspecific neighbours persist, other species might be advantaged, and diversity might be maintained through legacy effects. We examined legacy effects in a mapped forest by modelling the survival of 37,212 trees of 23 species using four neighbourhood properties: living conspecific, living heterospecific, legacy conspecific (dead conspecifics) and legacy heterospecific densities. Legacy conspecific effects proved nearly four times stronger than living conspecific effects; changes in annual survival associated with legacy conspecific density were 1.5% greater than living conspecific effects. Over 90% of species were negatively impacted by legacy conspecific density, compared to 47% by living conspecific density. Our results emphasize that legacies of trees alter community dynamics, revealing that prior research may have underestimated the strength of density dependent interactions by not considering legacy effects., (© 2024 John Wiley & Sons Ltd.)

Objective: Survivors of breast cancer with persistent cancer-related fatigue (CRF) report less exercise participation compared with survivors of breast cancer without CRF. Although CRF predicts other domains of self-efficacy among survivors, the effect of CRF on exercise self-efficacy (ESE)-an important predictor of exercise participation-has not been quantified. This study examined the relationship between CRF, ESE, and exercise participation and explored the lived experience of engaging in exercise among survivors of breast cancer with persistent CRF., Methods: Fifty-eight survivors of breast cancer (3.7 [SD = 2.4] years after primary treatment) self-reported CRF, ESE, and exercise participation (hours of moderate-intensity exercise per week). Regression and mediation analyses were conducted. Survivors who reported clinically significant CRF and weekly exercise were purposively sampled for 1-on-1 interviews (N = 11). Thematic analysis was performed across participants and within higher versus lower ESE subsets., Results: Greater CRF predicted lower ESE (β = -0.32) and less exercise participation (β = -0.08). ESE mediated the relationship between CRF and exercise participation (β = -0.05, 95% CI = -0.09 to -0.02). Qualitative data showed that survivors of breast cancer with higher ESE perceived exercise as a strategy to manage fatigue, described self-motivation and commitment to exercise, and had multiple sources of support. In contrast, survivors with lower ESE described less initiative to manage fatigue through exercise, greater difficulty staying committed to exercise, and less support., Conclusions: Survivors of breast cancer with persistent CRF may experience decreased ESE, which negatively influences exercise participation. Clinicians should screen for or discuss confidence as it relates to exercise and consider tailoring standardized exercise recommendations for this population to optimize ESE. This may facilitate more sustainable exercise participation and improve outcomes., Impact: This study highlights the behavioral underpinnings of CRF as a barrier to exercise. Individualized exercise tailored to optimize ESE may facilitate sustainable exercise participation among survivors of breast cancer with CRF. Strategies for clinicians to address ESE are described and future research is suggested., Lay Summary: Women with fatigue after breast cancer treatment may have lower confidence about their ability to engage in exercise. Individually tailoring exercise to build confidence as it relates to exercise may result in more consistent exercise and better health-related outcomes., (© The Author(s) 2022. Published by Oxford University Press on behalf of the American Physical Therapy Association.)

Background: Chemotherapy-induced peripheral neuropathy (CIPN) is considered a primary mechanism of imbalance among women diagnosed with breast cancer. Recent evidence, however, suggests that cancer-related fatigue (CRF) may also influence balance., Purpose: Examine the contributions of CRF and CIPN to static and dynamic balance before and after a period of fatiguing exercise., Methods: This is a secondary analysis of data examining functional differences between women with breast cancer with and without persistent CRF. Postural sway was measured during static standing and the rising phase of an instrumented sit-to-stand (ISTS) before and after exercise. Regression analyses were performed to determine how CRF and severity of CIPN predicted sway and how much variance was attributable to each., Results: Greater CRF predicted increased pre-, p =.04, and post-exertional, p =.02, static sway in the anterior-posterior plane. CRF accounted for 10.5% and 9.5% of the variance in pre- and post-exertional sway (respectively) compared to the 0.9% and 1.4% accounted for by CIPN severity which was not a significant predictor. After exercise, greater CRF predicted smaller, more conservative, anterior weight shifting during the ISTS, p =.01, and accounted for 6.6% of the variance in sway compared to 3% attributed to CIPN which was not a significant predictor., Limitations: This analysis is limited by its small and demographically homogenous sample., Conclusions: These results suggest that CRF may influence balance independent of CIPN symptoms. While CIPN remains a risk factor for imbalance in this population, CRF warrants consideration in clinical practice and research as a mechanism of postural instability.

Deep root systems that extend into moist soil can significantly increase plant productivity. Here, the components of soil-grown root systems of wheat, barley and triticale are characterized, and types and water conducting potential of deep roots in the field are assessed. Root system components were characterized in plants grown in soil in PVC tubes, based on their origin and number and the arrangement of xylem tracheary elements (XTE) viewed using fluorescence microscopy. A new nomenclature is proposed. Deep roots were harvested in the field, and root types of the current crop and remnant roots from previous crops were identified by fluorescence and cryo-scanning electron microscopy. Four types of axile (framework) and five types of branch root were distinguished in the three cereals. Six per cent of deep roots were axile roots that originated from the base of the embryo; 94% were branch roots, of which 48% had only two XTE (10 microm diameter), and thus potentially low axial flow. Only 30% of roots in the cores were from the current crop, the remainder being remnants. Selection for more deep-penetrating axile roots and increased vascular capacity of deep branches is of potential benefit. Conventional root-length density measurements should be interpreted and applied cautiously.