The effects of exercise training on inflammatory markers in children and adolescents: A systematic review and meta-analysis.

INTRODUCTION AND AIM: Exercise training is effective for improving cardiometabolic health in children and adolescents, but less is known about its impact on inflammatory markers. We therefore, undertook a systematic review and meta-analysis to investigate the role of exercise training on pro-inflammatory cytokines including interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-α), and C-reactive protein (CRP) in children and adolescents. METHOD: A comprehensive search was conducted in three electronic databases including PubMed, Web of Science, and Scopus, from inception to December 2023 to identify exercise trials with and without control groups, involving participants with mean ages ranging from ≥ 6 to < 18 years, of age with measurements of at least one of the following pro-inflammatory cytokines IL-6, TNF-α, or CRP. Standardized mean differences (SMD) and 95 % confidence interval (ICs) were calculated using random effects models. RESULTS: Thirty-eight studies involving 2043 children and adolescents were included. The results show that exercise training resulted in significant reductions in IL-6 [SMD: -0.44; 95 % CI: -0.68, -0.21; P = 0.001] and CRP [SMD: -0.28; 95 % CI: -0.41, -0.16; P = 0.001], but not TNF-α [SMD: -0.15; 95 % CI: -0.38, -0.07; P = 0.19]. Subgroup analyses showed that IL-6 and CRP were reduced with aerobic training in adolescents, as was CRP with high-intensity interval training. CONCLUSION: These results provide evidence that exercise training is effective for reducing IL-6 and CRP in adolescents, but not in children, and any benefits may be modulated by the type of exercise performed.

Effects of low-carbohydrate diets, with and without caloric restriction, on inflammatory markers in adults: a systematic review and meta-analysis of randomized clinical trials.

Low-carbohydrate diets (LCDs) have gained interest due to their favorable effects on health outcomes, such as inflammation. However, further research is needed to ascertain the overall effects of LCDs on inflammatory parameters, but at the same time considering weight loss and calorie intake. Thus, a systematic review and meta-analysis of randomized clinical trials was performed to investigate the effects of LCDs compared with low-fat diets (LFDs), with and without caloric restriction, on inflammatory markers in adults. PubMed, Scopus, and Web of Science were searched through March 2022 to select intervention studies addressing LCDs vs. LFDs, in which the following circulating inflammatory markers were used: C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), and interleukin (IL-6). Analyses were conducted comparing LCDs vs. LFDs through weighted mean differences (WMD) or standardized mean differences (SMD) and 95% confidence intervals (95% CIs) using random effects models. The systematic review and meta-analysis included a total of 51 studies with a total sample of 4,164 adults, with or without other chronic diseases. Intervention durations ranged from 2-144 weeks. LCDs, compared with LFDs, significantly decreased body weight [WMD = -1.35%, p = 0.001], CRP [SMD = -0.1, p = 0.03], and IL-6 [SMD = -0.15, p = 0.09]. However, LCDs did not significantly decrease TNF-α [SMD = -0.02, p = 0.7] compared to LFDs. In conclusion, LCDs have a beneficial effect on markers of inflammation by decreasing CRP and IL-6; this effect has an association with weight loss. However, LCDs were not more effective than LFDs in decreasing TNF-α.

Influence of different modes of exercise training on inflammatory markers in older adults with and without chronic diseases: A systematic review and meta-analysis.

INTRODUCTION: Ageing can be accompanied by increased inflammation, which contributes to the development of sarcopenia. Exercise training could be effective for preventing sarcopenia and mitigate inflammation and thus a viable intervention in ageing. Therefore, we performed a systematic review and meta-analysis to investigate the effects of exercise training on markers of inflammation including interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and C-reactive protein (CRP) in older adults (≥65 years). Exercise-based interventions are most successful in preventing the decline in skeletal muscle mass and in preserving or ameliorating functional capacities with increasing age. METHOD: PubMed and Web of Science were searched through to December 2021 using "exercise", "inflammatory markers", "elderly", and "randomized controlled trial" to identify randomized trials evaluating the effects of exercise training versus control groups on IL-6, TNF-α, and CRP in older adults with mean ages ≥ 65 yrs. Standardized mean differences (SMD) and 95% confidence intervals (95% CIs) were determined using random effects models. RESULTS: Forty studies involving 49 trials and 1,898 older adults were included in the meta-analysis. Overall, exercise training reduced IL-6 [-0.17 (95% CI -0.32 to -0.02), p = 0.02], TNF-α [-0.30 (95% CI -0.46 to -0.13), p = 0.001], and CRP [-0.45 (95% CI -0.61 to -0.29), p = 0.001]. Subgroup analyses showed that IL-6 was reduced significantly by combined training, TNF-α by aerobic training, and CRP by aerobic, resistance, and combined training. In addition, exercise training reduced IL-6 and TNF-α in older adults with chronic diseases, and CRP in older adults with and without chronic diseases. CONCLUSION: The current results highlight that exercise training, regardless of exercise type, has small to moderate beneficial effects on markers of inflammation in older adults, particularly in those with chronic diseases.

Effectiveness of supplementation with date seed (Phoenix dactylifera) as a functional food on inflammatory markers, muscle damage, and BDNF following high-intensity interval training: a randomized, double-blind, placebo-controlled trial.

PURPOSE: High-intensity interval training (HIIT) is one of the most effective protocols, even though acute HIIT causes inflammatory and oxidative damage. The aim of this study was to examine the effect of date seeds powder (DSP) during HIIT sessions on inflammation markers, oxidants and antioxidants, brain-derived neurotrophic factor (BDNF), exercise-induced muscle damage, and body composition. MATERIAL AND METHODS: Thirty-six recreational runners (men and women), aged 18-35 years, were randomly assigned to consume 26 g/day of DSP or wheat bran powder during HIIT workouts for a period of 14 days. At baseline, at the end of the intervention, and 24 h after the intervention, blood samples were obtained to determine inflammatory, oxidant/antioxidant, and muscle damage markers, as well as BDNF. RESULTS: DSP supplementation resulted in a significant downward trend in high-sensitivity C-reactive protein (Psupplement × time = 0.036), tumor necrosis factor alpha (Psupplement × time = 0.010), interleukin-6 (Psupplement × time = 0.047), malondialdehyde (Psupplement × time = 0.046), creatine kinase (Psupplement × time = 0.045), and lactate dehydrogenase (Psupplement × time = 0.040) after the intervention, as well as a significant increase in total antioxidant capacity (Psupplement × time ≤ 0.001). However, interleukin-10 (Psupplement × time = 0.523), interleukin-6/interleukin-10 (Psupplement × time = 0.061), BDNF (Psupplement × time = 0.160), and myoglobin (Psupplement × time = 0.095) levels did not change significantly in comparison to the placebo group. Moreover, analysis demonstrated that DSP supplementation over 2 weeks had no significant effect on body composition. CONCLUSION: During the 2 weeks of the HIIT protocol, the consumption of date seed powder by participants who had engaged in moderate or high physical activity alleviated inflammation and muscle damage. ETHICS AND DISSEMINATION: This study was approved by the Medical Ethics Committee of TBZMED (No.IR.TBZMED.REC.1399.1011). TRIAL REGISTRATION: Iranian Registry of Clinical Trials website ( www.IRCt.ir/ , IRCT20150205020965N9).

The effects of camelina sativa oil and high-intensity interval training on liver function and metabolic outcomes in male type 2 diabetic rats.

Objectives: The purpose of this study was to evaluate the independent and combined effects of camelina sativa oil and high-intensity interval training (HIIT) on liver function, and metabolic outcomes in streptozotocin-induced diabetic rats. Methods: Forty male Wistar rats were randomly assigned to five equal groups (8 per group): Normal control (NC), diabetic control (DC), diabetic + camelina sativa oil (300 mg/kg by oral gavage per day; D + CSO), diabetic + HIIT (running on a treadmill 5 days/week for 8 weeks; D + HIIT), diabetic + camelina sativa oil + HIIT (D + CSO + HIIT). Results: In all three intervention groups (D + CSO, D + HIIT, and D + CSO + HIIT) compared to the DC, hepatic TNF-α, MDA, and histopathology markers, decreased and hepatic PGC-1α, and PPAR-γ increased (p < 0.05). However, the effect of D + CSO was greater than D + HIIT alone. Hepatic TG decreased significantly in D + HIIT and D + CSO + HIIT compared to other groups (p < 0.001). Fasting plasma glucose in all three intervention groups (D + CSO, D + HIIT, and D + CSO + HIIT) and HOMA-IR in D + CSO and D + CSO + HIIT were decreased compared to DC (p < 0.001). Only hepatic TAC and fasting plasma insulin remained unaffected in the three diabetic groups (p < 0.001). Overall, D + CSO + HIIT had the largest effect on all outcomes. Conclusions: At the doses and treatment duration used in the current study, combination of CSO and HIIT was beneficial for reducing liver function and metabolic outcomes other than CSO and HIIT alone.

The impact of exercise training versus caloric restriction on inflammation markers: a systemic review and meta-analysis.

Obesity is associated with an increased risk of chronic, low-grade systematic inflammation for which exercise training (EX) and caloric restriction (CR) are potential treatments. We therefore performed a systematic meta-analysis to compare the effect of EX vs. CR and EX + CR vs. CR on inflammation markers in overweight and obese individuals. PubMed, Scopus, Web of Science and the Cochrane were searched up to April 2020 for EX vs. CR or EX + CR vs. CR interventions studies on inflammatory makers i.e. CRP, IL-6 and TNF-α in overweight and obese individuals. Standardized mean differences and 95% confidence intervals were calculated. Thirty two articles (reporting 38 trials) involving 2108 participants were included in the meta-analysis. Based on studies that directly compared EX and CR, there were no evidence for an effect of EX on IL-6 (p = 0.20) and TNF-α (p = 0.58), when compared with a CR. However, when compared to EX, CR has a statistically greater benefit on CRP (p = 0.01). In those studies, directly comparing EX + CR and CR, EX + CR caused a larger decrease in TNF-α (p = 0.002) and IL-6 (p = 0.02) and tended to decrease CRP (p = 0.06) when compared with CR. These results suggest that a combination of EX and CR may be more effective than CR alone at reducing inflammatory cytokines and CRP in overweight and obese individuals.

The impact of high-intensity interval training on inflammatory markers in metabolic disorders: A meta-analysis.

INTRODUCTION: High-intensity interval training (HIIT) is considered a time-efficient strategy to improve metabolic health. We performed a systematic meta-analysis to assess the effects of HIIT on inflammatory markers and adipo-cytokines compared with control conditions (CON) or moderate-intensity continuous training (MICT) in individuals with metabolic disorders. METHODS: Up to January 2020, electronic databases were searched for HIIT interventions based on populations with metabolic disorders including diabetes, metabolic syndrome, polycystic ovary syndrome, non-alcoholic fatty liver disease or overweight/obesity, with outcome measurements that included IL-6, TNF-α, CRP, leptin or adiponectin and training ≥2 weeks. Random-effects models were used to aggregate a mean effect size (ES), 95% confidence intervals (Cis), and potential moderators were explored. RESULTS: Twenty-nine studies involving 841 participants were included in the meta-analysis. HIIT improved circulating adiponectin (P = .02), leptin (P = .02), and TNF-α (P = .003) when compared to CON. There were no differences between groups in IL-6 and CRP. Intervention duration was a significant moderator for the effect of HIIT on IL-6, and leptin (P < .05). CONCLUSION: High-intensity interval training improves circulating TNF-α, leptin and adiponectin, thereby indicating that it may be an effective and time-efficient intervention for controlling low-grade inflammation in individuals with metabolic disorders.