Psychological and Physiological Responses across Six Weeks of HIIT and MICT in Previously Inactive Young Adults

International Journal of Exercise Science 16(5): 756-769, 2023. High-intensity interval training (HIIT) is suggested as a public health strategy to increase engagement in, and adherence to, physical activity. However, debate exists regarding the efficacy in inactive individuals. PURPOSE: To determine the physiological and psychological responses to three weeks of supervised and three weeks of unsupervised HIIT or moderate-intensity continuous training (MICT) in previously inactive adults. METHODS: Young adults (n = 20; 21.4 ± 2.2 years; 13 females) were randomized to six weeks of HIIT or MICT. Pre- and post-testing included anthropometric measures, an incremental exercise test, and body composition. Psychological outcomes (i.e., perceived competence, self-efficacy, and enjoyment) were assessed at the end of the first, ninth, and eighteenth training sessions. Differences in physiological outcomes were analyzed using repeated measures factorial ANCOVAs. Differences in psychological outcomes were analyzed using repeated measures factorial ANOVAs. RESULTS: Maximal oxygen consumption (Δ 2.8 ml·kg-1·min-1; p = .03) and peak power output (Δ 20.2 W; p = .01) improved over time with no group differences (p \u3e .05). No changes occurred in body composition or self-efficacy (p ≥ .27). Perceived competence increased with supervised training (p = .01) with no further increases during unsupervised training. There was no difference in enjoyment across supervised training (p = .07), but enjoyment decreased during unsupervised training (p = .003). CONCLUSIONS: Cardiorespiratory fitness improved comparably for HIIT and MICT but with a shorter time commitment for HIIT. Perceived competence increased across supervised training suggesting it may be important to provide support at the beginning of an exercise intervention

The effect of ageing on macrophage Toll-like receptor-mediated responses in the fight against pathogens

The cellular changes during ageing are incompletely understood yet immune system dysfunction is implicated in the age-related decline in health. The acquired immune system shows a functional decline in ability to respond to new pathogens whereas serum levels of cytokines are elevated with age. Despite these age-associated increases in circulating cytokines, the function of aged macrophages is decreased. Pathogen-associated molecular pattern receptors such as Toll-like receptors (TLRs) are vital in the response of macrophages to pathological stimuli. Here we review the evidence for defective TLR signalling in normal ageing. Gene transcription, protein expression and cell surface expression of members of the TLR family of receptors and co-effector molecules do not show a consistent age-dependent change across model systems. However, there is evidence for impaired downstream signalling events, including inhibition of positive and activation of negative modulators of TLR induced signalling events. In this paper we hypothesize that despite a poor inflammatory response via TLR activation, the ineffective clearance of pathogens by macrophages increases the duration of their activation and contributes to perpetuation of inflammatory responses and ageing

Heart Rate and Rating of Perceived Exertion During High-Intensity Interval Training: Implications for Prescribing Intensity

High-intensity interval training (HIIT) is a popular and effective time-efficient alternative to moderate-intensity continuous training for improving cardiorespiratory fitness. However, there is limited research investigating the most effective and practical way to prescribe training intensities for HIIT. PURPOSE: To determine heart rate (HR) and rating of perceived exertion (RPE) responses across a bout of HIIT. Additionally, the relationship between HR and RPE was examined. METHODS: Young adults (n=16; age 21.8±1.4 years; 10 females) visited the lab on two separate occasions. At the first visit, participants completed an incremental exercise test on a cycle ergometer to determine peak power output (PPO). During the second lab visit participants completed the HIIT protocol which involved ten, 1-minute bouts of cycling at 80% PPO interspersed with 1-minute of active rest cycling at 20% PPO. HR and RPE were measured at the end of the first, fifth, and tenth work intervals using the CR10 Borg scale. Differences in HR and RPE across the training session were determined using one-way repeated measures ANOVAs. Pearson correlations were utilized to assess relationships. RESULTS: HR and RPE both significantly increased from the first (HR 157±16 bpm; RPE 5.0±1.8) to the fifth interval (HR 174±14 bpm; RPE 6.8±1.7; p0.05 for both). There were no significant relationships between HR and RPE for any of the time points (r=-0.01 to -0.34, p=0.19 to 0.89) or the average of the session (r=0.37, p=0.16). CONCLUSIONS: HR and RPE both increased initially during the HIIT session with no further increase after mid-point. There were no significant relationships between HR and RPE. These findings suggest that RPE, using the CR10 Borg scale, may not replicate HR for determining intensity during HIIT. Future research may be beneficial to determine a practical method for prescribing exercise intensity during HIIT

Behavioral correlates between daily activity and sociality in wild and captive origin African lions

Study of behavioral correlations within and across populations has long been of interest to ethologists. An exploration of behavioral correlations between sociality and behavior of African lions (Panthera leo) was undertaken to examine if this approach is better able to reveal important aspects of lion behavior not easily discernible by looking at these behaviors separately. Resting behavior and received play interactions were correlated in 2 captive-origin prides and one wild pride, attributable to the involvement of cubs and sub-adults. Direct and exploratory movement was negatively correlated with groom centrality in 2 of the 3 prides, due to adults engaging in high levels of both of these activities. Exploration of these behavioral correlations highlighted the differences between age-groups in activity and sociality, facilitating the understanding of the complex behavior and interactions of lions. In addition, the finding of similar behavioral correlations between captive-origin and the wild prides provides confidence in the suitability if captive-origin candidates for ex-situ release. This is imperative to ensure the success of sub-groups and prides under an ex-situ reintroduction program

Working in partnership with vulnerable families: The experience of child and family health practitioners

Family circumstances in infancy are persistent and powerful determinants of children's physical and mental health, influencing inequalities that trace from childhood through to adulthood. While the social factors that perpetuate patterns of inequality are more complex than can be addressed through single interventions, child and family health (CFH) services represent crucial sites where trajectories of inequality can be disrupted. In particular, approaches that foster opportunities for practitionerparent engagement that challenge traditional hierarchical health care practice, such as the Family Partnership Model (FPM), are recommended as ways of addressing disadvantage. Little is known about how practitioners implement models of working in partnership with families and, consequently, there is a gap in understanding how best to develop and sustain these new CFH practices. This paper reports a research project that investigated the experiences of 25 health professionals working within a FPM framework with vulnerable families. Through discussion of four key themes redefining expertise, changing practices, establishing new relationships with parents and the complexities of partnership practice the paper offers first-hand accounts of reframing practices that recognise the needs, skills and expertise of parents and thus contribute to empowerment of families. © 2011 La Trobe University

CD4+ T cell surface alpha enolase is lower in older adults

To identify novel cell ageing markers in order to gain insight into ageing mechanisms, we adopted membrane enrichment and comparison of the CD4+ T cell membrane proteome (purified by cell surface labelling using Sulfo-NHS-SS-Biotin reagent) between healthy young (n=9, 20-25y) and older (n=10; 50-70y) male adults. Following two-dimensional gel electrophoresis (2DE) to separate pooled membrane proteins in triplicates, the identity of protein spots with age-dependent differences (p1.4 fold difference) was determined using liquid chromatography-mass spectrometry (LC-MS/MS). Seventeen protein spot density differences (ten increased and seven decreased in the older adult group) were observed between young and older adults. From spot intensity analysis, CD4+ T cell surface α-enolase was decreased in expression by 1.5 fold in the older age group; this was verified by flow cytometry (n=22) and qPCR with significantly lower expression of cellular α-enolase mRNA and protein compared to young adult CD4+ T cells (p<0.05). In an independent age-matched case-control study, lower CD4+ T cell surface α-enolase expression was observed in age-matched patients with cardiovascular disease (p<0.05). An immune-modulatory role has been proposed for surface α-enolase and our findings of decreased expression suggest that deficits in surface α-enolase merit investigation in the context of immune dysfunction during ageing and vascular disease

Integrated approach of the citizen’s role in relation to the public services

The paper achieves an integrated, interdisciplinary approach of the citizens’ roles related to public service providers. The contemporary public service development awards multiple roles to the citizen, interacting with the activities of design, decision-making, production, delivery or assessment, specific for various stages of the life cycle of the public services. Such an approach substantiates the public marketing strategies and it integrates aspects concerning service delivery in the private secto

Kidney disease in nail–patella syndrome

Nail–patella syndrome (NPS) is a pleiotropic autosomal-dominant disorder due to mutations in the gene LMX1B. It has traditionally been characterized by a tetrad of dermatologic and musculoskeletal abnormalities. However, one of the most serious manifestations of NPS is kidney disease, which may be present in up to 40% of affected individuals. Although LMX1B is a developmental LIM-homeodomain transcription factor, it is expressed in post-natal life in the glomerular podocyte, suggesting a regulatory role in that cell. Kidney disease in NPS seems to occur more often in some families with NPS, but it does not segregate with any particular mutation type or location. Two patterns of NPS nephropathy may be distinguished. Most affected individuals manifest only an accelerated age-related loss of filtration function in comparison with unaffected individuals. Development of symptomatic kidney failure is rare in this group, and proteinuria (present in approximately one-third) does not appear to be progressive. A small minority (5–10%) of individuals with NPS develop nephrotic-range proteinuria as early as childhood or young adulthood and progress to end-stage kidney failure over variable periods of time. It is proposed that this latter group reflects the effects of more global podocyte dysfunction, possibly due to the combination of a mutation in LMX1B along with an otherwise innocuous polymorphism or mutation involving any of several genes expressed in podocytes (e.g. NPHS2, CD2AP), the transription of which is regulated by LMX1B