High-Intensity Functional Training Improves Cardiorespiratory Fitness and Neuromuscular Performance Without Inflammation or Muscle Damage.

ABSTRACT: Posnakidis, G, Aphamis, G, Giannaki, CD, Mougios, V, Aristotelous, P, Samoutis, G, and Bogdanis, GC. High-intensity functional training improves cardiorespiratory fitness and neuromuscular performance without inflammation or muscle damage. J Strength Cond Res 36(3): 615-623, 2022-We examined the effects of high-intensity functional training (HIFT) on cardiorespiratory and neuromuscular performance, as well as on inflammatory and muscle damage markers. Thirteen physically active healthy volunteers (aged 28.3 ± 3.8 years, 5 men and 8 women) underwent 8 weeks of a group HIFT program performed 3 times per week. Each session consisted of 4 rounds of a 9-exercise circuit (30-second exercise and 15-second recovery). During the first and last weeks of training, venous blood was sampled daily to monitor changes in serum C-reactive protein (CRP) and creatine kinase (CK). After 8 weeks of HIFT, body fat decreased by 0.64 ± 1.01 kg (p = 0.041), maximal oxygen uptake improved by 1.9 ± 2.2 ml·kg-1·min-1 (p = 0.009), countermovement jump by 2.6 ± 1.5 cm (p = 0.001), bench press 1-repetition maximum (1RM) by 4.5 ± 3.8 kg (p = 0.001), maximum number of bench press repetitions at 65% 1RM by 4 ± 5 repetitions (p = 0.03), and abdominal muscle endurance by 6 ± 4 repetitions (p < 0.001). In both week 1 and week 8 of training, CK increased mildly in the morning after the first session of the week (main effect for day, p = 0.008), whereas no significant changes were observed in CRP (p = 0.31). During week 8, CK on all days was ∼32% lower compared with week 1 (160 vs. 235 U·L-1; main effect of week 1 vs. week 8, p = 0.027), whereas CRP remained unchanged (p = 0.225). This HIFT program was effective in improving cardiorespiratory and neuromuscular physical fitness without causing significant inflammation or muscle damage in physically active subjects.

Effects of controlled dehydration on sleep quality and quantity: A polysomnographic study in healthy young adults.

Dehydration is associated with several alternations in body homeostasis involving both physiological and mental aspects. In addition some studies have reported a negative effect of dehydration on subjectively assessed sleep-related parameters. The aim of the current study was to examine for the first time the effect of controlled dehydration on sleep quality and quantity using the gold-standard method of polysomnography. Twelve healthy male volunteers participated in this study (23.4 ± 0.8 years). Participants performed an in-house full polysomnographic assessment in two different occasions taking place in random order: (i) in a dehydrated state; and (ii) in a euhydrated state. In the dehydration scenario, the participants were allowed to consume only 1.25 L of non-caffeinated fluids, while during the euhydrated state participants had to drink at least 3 L of non-caffeinated fluids during the last 24 hr before the polysomnographic study. Urine specific gravity was assessed by refractrometry on collection day in order to assess hydration status. Participants who did not fulfil the hydration criteria were rescheduled. All participants successfully completed the two polysomnographic studies without any complaints or adverse effects reported. No significant differences were found in any of the examined indices of sleep quality and quantity between the dehydration and euhydration scenarios (p > .05). This is the first study to show that controlled mild dehydration does not seem to affect sleep quality and quantity in young healthy adults. More research is necessary to further verify these conclusions and assess whether other parameters are involved in the manifestation of sleep disturbances.

Restless legs syndrome in Multiple Sclerosis patients: a contributing factor for fatigue, impaired functional capacity, and diminished health-related quality of life.

Objectives Restless legs syndrome (RLS) symptoms are common in Multiple Sclerosis (MS) patients. The aim of the current study was to examine for the first time whether RLS could affect the functional capacity and various contributing parameters related to quality of life and fatigue in MS patients. Methods According to their RLS status, 50 relapsing-remitting MS patients were divided into the RLS (n = 10) and non-RLS groups (n = 40). Specific questionnaires were used in order to assess the health-related quality of life (HRQoL), fatigue levels, sleep quality, daily sleepiness, and depression symptoms of the patients. Functional capacity was examined using a battery of functional tests. Total body and visceral fat levels were assessed via bioelectrical impedance analyzers. Results Sleep quality, depression, fatigue, and HRQoL levels were found to be significantly worse in the patients with RLS compared to their free-RLS counterparts (P < 0.05). In addition, patients with RLS were found to exhibit further impairments in their performance in various functional tests related mainly with strength levels of lower extremities (P < 0.05). Finally, the patients with RLS were found to have significantly higher both total and trunk fat levels compared to patients without RLS (P < 0.05). A strong correlation was observed between the severity of RLS symptoms, sleep quality, fatigue, and QoL levels. Discussion It seems that RLS contributes even further to impairments on sleep quality, fatigue, functional capacity, and therefore HRQoL levels in relapsing-remitting MS patients, whilst for the first time a link between high fat levels has been revealed.