Caffeine, which is widely used for enhancing athletic performance, has been suggested to have a positive impact on cognition via stimulating the brain. However, no study published to date has explored the effects of different doses of caffeine ingestion on brain activation via cortical hemodynamics. The purpose of the present crossover, double-blind study was to investigate the effects of low, moderate, and high doses of caffeine ingestion on cognitive performance and brain activation. Ten healthy male subjects ingested placebo or caffeine (3, 6, or 9 mg/kg body mass). The effects of each treatment condition were evaluated by Stroop tasks before and 60 min after the ingestion of caffeine. Reaction time (RT) and accuracy of responses to congruent and incongruent stimuli were assessed. As an index of brain activation with cognition, levels of oxygenated hemoglobin (HbO) were measured via near-infrared spectroscopy. A 4 × 2 mixed ANOVA revealed that there were significant interaction effects for RT in both incongruent and congruent conditions (P < 0.01, Pη² = 0.384; P < 0.05, Pη² = 0.259; and P < 0.05, Pη² = 0.309). Both 3 and 6 mg/kg of caffeine ingestion significantly decreased RT to incongruent stimuli. The only dose of caffeine to decrease RT in response to congruent stimuli was 3 mg/kg. None of the doses of caffeine administered affected accuracy of responses to incongruent or congruent stimuli. Under the congruent stimulus condition, ingestion of 3 mg/kg of caffeine significantly increased mean HbO in the dorsolateral prefrontal cortex, frontal pole area, ventrolateral prefrontal cortex (P < 0.01, Pη² = 0.319; P < 0.05, Pη² = 0.263; and P < 0.05, Pη² = 0.259, respectively). None of the doses of caffeine investigated affected HbO under the incongruent stimulus condition. Ingestion of low-dose caffeine has greater effects on cognition and brain activation than moderate and high doses of caffeine, suggesting that low-dose caffeine may be a selective supplement in enhancing executive function and prefrontal activities.

To date, no study has examined the effects of caffeine on prolonged intermittent exercise performance that imitates certain team-sports, and the suitable concentration of caffeine for improved intermittent exercise performance remains elusive. The purpose of the present cross-over, double-blind preliminary study was to investigate effects of low, moderate, and high doses of caffeine ingestion on intermittent exercise performance and cognition. Ten males performed a familiarization session and four experimental trials. Participants ingested capsules of placebo or caffeine (3, 6, or 9 mg/kg) at 1 h before exercise, rested quietly, and then performed cycling for 2 × 30 min. The cycling protocol consisted of maximal power pedaling for 5 s (mass × 0.075 kp) every minute, separated by unloaded pedaling for 25 s and rest for 30 s. At pre-ingestion of capsules, 1 h post-ingestion, and post-exercise, participants completed the Stroop task. The mean power-output (MPO), peak power-output (PPO), and response time (RT) in the Stroop task were measured. Only 3 mg/kg of caffeine had positive effects on the mean PPO and MPO; 3 mg/kg caffeine decreased RTs significantly in the incongruent and congruent conditions. These results indicate that the ingestion of low-dose caffeine had greater positive effects on the participants’ physical strength during prolonged intermittent exercise and cognition than moderate- or high-dose caffeine.

Global warming has intensified the health risks associated with heat stress, such as heatstroke and dehydration, underscoring the importance of understanding heat acclimatization (HA). HA involves physiological, psychological, and structural adaptations to prolonged high temperatures, improving heat tolerance and reducing heat-related harm. A key player in this process is HSP70, a conserved protein essential for maintaining cellular balance, regulating cell death, and controlling waste removal. While HA mechanisms like temperature regulation and metabolic changes are well studied, the relationship between HSP70 and brain self-repair processes remains unclear. This study uncovers how HSP70, and these processes work together to aid heat adaptation, reveals how environmental stress drives inherited resilience through genetic adjustments, and offers insights for designing targeted health strategies to protect vulnerable populations, connecting lab discoveries to global health needs.

Intellectual disability (ID) is a prevalent neurodevelopmental disorder characterized by neurodevelopmental defects such as the congenital impairment of intellectual function and restricted adaptive behavior. However, genetic studies have been significantly hindered by the extreme clinical and genetic heterogeneity of the subjects under investigation. With the development of gene sequencing technologies, more genetic variations have been discovered, assisting efforts in ID identification and treatment. In this review, the physiological basis of gene variations in ID is systematically explained, the diagnosis and therapy of ID is comprehensively described, and the potential of genetic therapies and exercise therapy in the rehabilitation of individuals with intellectual disabilities are highlighted, offering new perspectives for treatment approaches.

Neuropathic pain (NP) is a prevalent clinical condition resulting from diseases or injuries affecting the somatosensory system. Conventional analgesics often exhibit limited efficacy, leading to suboptimal therapeutic outcomes. The pathogenesis of NP is complex and involves multiple mechanisms. The existing evidence suggests that maladaptive neuronal plasticity plays a central role in NP development. Additionally, emerging research highlights the contribution of neuroinflammatory responses mediated by glial cells in the onset of NP and associated sensory hypersensitivity. Among non-invasive neuromodulation techniques, transcranial direct current stimulation (tDCS) has gained prominence as a potential treatment for NP. Numerous studies have demonstrated its analgesic effects; however, the precise regulatory mechanisms remain unclear. The current evidence indicates that tDCS may alleviate NP by enhancing glial–neuronal interactions, which suppress nociceptive signaling pathways and reduce pain sensitivity. The reciprocal modulation between tDCS-mediated anti-inflammatory actions, as evidenced by decreased levels of pro-inflammatory cytokines and increased levels of anti-inflammatory mediators, and its facilitation of adaptive neural plasticity represents a particularly compelling therapeutic axis. This review elucidates inflammatory regulation by tDCS as a fundamental mechanism for NP alleviation, while delineating important unresolved questions regarding these complex interactions.

The aim of this study was to investigate the effects of whole-body cold-water immersion (WCWI) and lower-limb cold-water immersion (LCWI) employed during a 15-min recovery period on the subsequent exercise performance as well as to determine the physiological and perceptual parameters in the heat (39°C). Eleven males performed team-sports-specific tests outdoors. The exercise program consisted of two identical exercise protocols (1 and 2) separated by a 15-min recovery period. The participants completed the same tests in each exercise protocol, in the following order: agility t test (t-test), 20-m sprint test (20M-ST), and Yo-Yo Intermittent Endurance Test Level 1 (Yo-Yo). During the recovery period, a 3-min recovery intervention of a passively seated rest (control, CON), WCWI, or LCWI was performed. The t-test and 20M-ST for the CON group were significantly longer during exercise protocol 2, but they were not significantly different between the two exercise protocols for the WCWI and LCWI groups. The completed Yo-Yo distance for the CON and LCWI groups was shorter during exercise protocol 2, but it was not significantly different between the two exercise protocols for the WCWI group. The chest temperature (T_chest), upper arm temperature (T_arm), thigh temperature (T_thigh), mean skin temperature (T_skin), and thermal sensation (TS) values were lower for the WCWI group than for the CON group; but only the T_thigh, T_skin, and TS values were lower for the LCWI group compared to the CON group. The T_chest, T_arm, T_skin, and TS values after the intervention were lower for the WCWI group than for the LCWI group. None of the three intervention conditions affected the core temperature (T_core), heart rate (HR), or rating of perceived exertion (RPE). These results suggest that WCWI at 15°C for 3 min during the 15-min recovery period attenuates the impairment of agility, sprint, and intermittent-endurance performance during exercise protocol 2, but LCWI only ameliorates the reduction of agility and sprint performance. Furthermore, the ergogenic effects of WCWI and LCWI in the heat are due, at least in part, to a decrease of the T_skin and improvement of perceived strain.