Responses to Low- and High-Intensity Exercise in Adolescents with Type 1 Diabetes in Relation to Their Level of VO2 Max

Impact of Dietary Intake and Cardiorespiratory Fitness on Glycemic Variability in Adolescents: An Observational Study

Background

Cardiorespiratory fitness (CRF), estimated by maximum oxygen consumption (VO2 max) during exercise, is worsening among adolescents and associated with a decline in metabolic health into adulthood. Glycemic patterns may provide a mechanism between CRF and health.

Objectives

This study assessed the feasibility of measuring glycemic patterns using continuous glucose monitoring (CGM) in adolescents, aged 14-22 y, to estimate the relationship between VO2 max and glucose patterns.

Methods

Healthy adolescents (n = 30) were recruited for a treadmill VO2 max test and to complete the following activities for 7-10 d: 1) wear a Dexcom G6 CGM, 2) complete ≥3 24-h dietary recalls, and 3) complete 1 at-home oral glucose tolerance test (OGTT, 75 g glucose). Glycemic patterns were extracted as mean glucose, the coefficient of variance, the mean amplitude of glycemic excursions, and the mean of daily differences. The 2-h glucose responses to the OGTT and individual meals were extracted. Statistical analyses evaluated the relationship between VO2 max and 1) overall glycemic patterns and 2) the maximum glucose level and AUC response to OGTT and meals, stratified by sex.

Results

Participant feasibility demonstrated that 90% completed CGM data (n = 27), 87% ≥7 d of CGM data (n = 26), 97% attempted OGTT (n = 29), and 93% completed ≥3 dietary recalls (n = 28). Most participants had normal BMI (70%) with an even distribution of sex (44% male). Males exhibited an inverse relationship between VO2 max and overall mean glucose (ß= -7.7, P = 0.04). Males demonstrated an inverse relationship between VO2 max and 1) maximum glucose (ß = -29, P = 0.006) and AUC (ß = -2702, P = 0.001) in response to the OGTT and 2) AUC (ß = -1293, P = 0.03) in response to meals. No association was observed between VO2 max and glucose patterns in females.

Conclusions

A sex-specific relationship between VO2 max and glycemic patterns was observed, suggesting a unique metabolic capacity during late adolescence by sex.This trial was registered at clinicaltrials.gov as NCT05845827.

Methods of Assessment of Physical Capacity in People with Diabetes Mellitus Type 1

BACKGROUND

The article aims to present the most popular methods of assessing physical capacity. Moreover, the article sheds light on the beneficial impact of improving physical capacity in people with Diabetes Mellitus type 1 (DM1).

METHODS

A computer-based literature search of PubMed, SCOPUS and Web of Science included studies up to September 2022.

RESULTS

The significant role of regular physical exertion could be observed in the group of people suffering from DM1, which implicates a positive correlation between the activity and the remission time. A suitable and objective indicator of sport influence on the organism is physical capacity (PC), which describes the efficiency of the cardiovascular system and its correlation between BMI, sex, and age. PC is mostly shown as VO2max. Well metabolically controlled DM1 is not a contraindication to stress test. Even though physical activity is closely related to human history, the range of research into the importance of PC is still limited to particular groups of patients, which presents an opportunity for further research and future conclusions.

CONCLUSIONS

Undertaking physical activities has a multidirectional influence on the organism. According to up-to-date knowledge, various methods of PC assessment are available. Patients can choose more easily accessible, simpler, and cheaper options like CRT, RT, and HST which do not need specialized equipment and skills. They can also decide on more advanced examinations like ergospirometry, where direct measurements of VO2max and other cardiorespiratory parameters are made.

A High intensity Interval training (running and swimming) and resistance training intervention on heart rate variability and the selected biochemical factors in boys with type 1 diabetes

OBJECTIVE

The purpose of this research is to investigate the effect of High Intensity Interval Training and Resistance training (HIITR) on heart rate variability (HRV), blood glucose, and plasma biomarkers levels in adolescents with type 1 diabetes (T1D).

RESEARCH DESIGN AND METHODS

24 boys with T1D (FBS: 274.66 ± 52.99, age: 15.2 ± 1.78 years, and BMI = 19.61 ± 1.11) and 12 healthy boys (FBS: 92.75 ± 5.22, age: 15.08 ± 1.67 years, and BMI = 20.26 ± 2.66) were divided into three groups: Diabetes Training (DT, n = 12), Diabetes Control (DC, n = 12), and Healthy Control (HC, n = 12). HRV (24 h) was computed in time and frequency domains, anthropometric, biochemical parameters at rest, and aerobic capacity (VO2peak) obtained during a graded exercise testing (GXT). All variables were evaluated at the baseline and following 12 weeks of exercise training, done 3 days weekly. The statistical method used for data analysis was analysis of covariance (ANCOVA) test.

RESULTS

HRV, Hemoglobin A1c (HbA1c) and Fasting blood sugar (FBS), VO2peak, norepinephrine (NEP), and HDL-C indicated significant differences between both T1D groups compared to HC at baseline (p < 0.001). BMI, LDL-C, TC, and TG parameters were similar in all groups. HRV parameters, VO2peak and HDL-C, and NEP were significantly improved by exercise training, and HbA1c and FBS levels were significantly reduced (p < 0.001). There is a negative and significant correlation between LF/HF Ratio Difference (post-test minus pre-test) and VO2Peak Difference variables (post-test minus pre-test) (p < 0.001).

CONCLUSIONS

The present study suggests the importance of early screening for CVD risk factors in adolescent males with T1D. Also, it was revealed HIITR training compared to other training patterns, and cardiovascular health improves via enhancement of autonomic modulation, VO2peak, plasma lipids, and catecholamine levels.

Association between high levels of physical activity and improved glucose control on active days in youth with type 1 diabetes

BACKGROUND

Sixty minutes per day of at least moderate to vigorous physical activity (MVPA) is recommended for children for a variety of physical and psychological reasons. Adherence to these guidelines is confounded by challenges with glucose control during exercise in type 1 diabetes (T1D).

OBJECTIVES

This study examined the potential association between physical activity level on active days and glucose control in youth with T1D.

METHODS

Blinded continuous glucose monitors (CGM: Abbott Libre Pro) and physical activity data as measured from a body monitor patch (Metria IH1) were collected for up to 3 weeks in youth aged 9-17 years with T1D. The association between physical activity levels, expressed as mean active metabolic equivalent minutes (MET-minutes) per day, with CGM-based mean glucose, percent time in range (TIR: 70-180 mg/dl), % time above range (TAR) and % time below range (TBR) were assessed using a linear regression model adjusted for age, gender, and baseline HbA1c.

RESULTS

Study participants were deemed physically active, as defined by at least 10 min of continuous moderate-to-vigorous activity, on 5.2 ± 1.9 days per week, with a median accumulated physical activity time of 61 [IQR: 37-145] minutes per day. Higher physical activity levels were associated with lower mean glucose levels (r = -0.36; p = 0.02) and lower TAR (r = -0.45; p = 0.002) on active days. Higher activity levels were also associated with greater TIR (r = 0.54; p < 0.001) without being associated with more, or less, TBR.

CONCLUSIONS

Higher amounts of physical activity are associated with improvements in TIR without significantly increasing TBR. These data suggest that youth ages 9-17 years with T1D can benefit from a high level of physical activity without undue fear of hypoglycemia.

PASTEC - a prospective, single-center, randomized, cross-over trial of pure physical versus physical plus attentional training in children with cancer

Despite recent improvements in survival rates in children with cancer, long-term toxicities remain a major concern. Physical activity could reduce the impact of long-term sequelae, notably in neuropsychological and physical areas. We report of a randomized trial of pure physical versus physical/attentional training in pediatric oncology patients. Twenty-two patients aged 6-18 y.o. were included, irrespective of their clinical diagnosis or treatment status, stratified by age and randomized 1:1 into pure physical vs. physical/attentional activity arms, with a cross-over at study midpoint. Neurological, motor and neuropsychological assessments were performed at inclusion, start, crossover and end of the program. Feasibility, defined as > 80% patients attending > 80% of sessions, was the primary endpoint. Secondary outcomes were improvements in neuropsychological and motor performance tests. While 68% of patients attended more than 80% of sessions during the pre-crossover phase of the study, this dropped to 36% post-crossover. Our study therefore failed to meet our primary endpoint. Nonetheless, significant improvements in anxiety (p<0.001), emotional control (p = 0.04), organization skills (p = 0.03), as well as motor deficit scores (p = 0.04) were observed. We noted no significant difference between the pure physical and the physical/attentional training arms, or when analyzing subgroups by age or sequence of intervention. We conclude that physical activity has a positive impact on anxiety, emotional and organizational aspects as well as motor deficits. Attendance dropped during the course of the study and motivational interventions should be included in future studies or equivalent programs.Supplemental data for this article is available online at https://doi.org/10.1080/08880018.2021.1994677 .

Effect of Nutritional Habits on the Glycemic Response to Different Carbohydrate Diet in Children with Type 1 Diabetes Mellitus

Unhealthy eating habits are associated with obesity, metabolic syndrome, and increased insulin resistance in young patients with type 1 diabetes mellitus (T1DM), and may impact the possible benefit from dietary interventions on glycaemic control. This study determines how nutritional patterns influence the quality of dietary intervention with a 30% or 50% carbohydrate diet in terms of glycaemic control measured with continuous glucose monitoring (CGM). Eating habits were obtained with a frequency-of-consumption questionnaire (FFQ-6) before the diet assessment. Altogether, we collected CGM and FFQ-6 data from 30 children (16 boys and 14 girls aged 10-17 years) with T1DM subjected to two consecutive 3-day nutritional plans. From these, 23 patients met the CGM data quality criteria for further analysis. Furthermore, high accuracy achieved in training (95.65%) and V-fold cross-validation (81.67%) suggest a significant impact of food habits in response to introduced nutritional changes. Patients who consumed more vegetables or grains (>4 times per day), more wheat products (>once per day), fewer fats (<1.5 times per day), and ranked fruit juice as the most common selection in the drinks category achieved glycaemic control more often after the introduction of a 30% carbohydrate diet, as opposed to those with different dietary patterns, whose glycaemic control was negatively impacted after switching to this diet. Additionally, the 50% carbohydrate diet was safe for all patients in the context of glycaemic control.