Clinical Outcomes Following a Change in Gestational Diabetes Mellitus Diagnostic Criteria Due to the COVID-19 Pandemic: A Case-Control Study.

BACKGROUND: Due to COVID-19, many centres adopted a change to the diagnosis of GDM. METHODS: A case-control study of antenatal patients between 1 April and 30 June in 2019 and 2020 looking at detection rates of GDM, use of medication, obstetric, and fetal outcomes. RESULTS: During COVID-19, the rate of positive GDM tests approximately halved (20% (42/210) in 2020 vs. 42.2% (92/218) in 2019, (p < 0.01)) with higher rates of requirement for insulin at diagnosis (21.4% (2020) vs. 2.2% (2019); p < 0.01), and at term (31% (2020) vs. 5.4% (2019); p < 0.01). and metformin at diagnosis (4.8% (2020) vs. 1.1% (2019); p < 0.01), and at term (14.3% (2020) vs. 7.6% (2019) p < 0.01), with no differences in birth outcomes. CONCLUSIONS: There was likely an underdiagnosis of GDM while women at a higher risk of hyperglycaemia were correctly identified. The GTT should be maintained as the gold-standard test where possible, with provisions made for social distancing during testing if required.

Higher fat oxidation during treadmill walking versus cycle ergometry in active women at equal RPE: a pilot study.

BACKGROUND: Muscle degrades fat and carbohydrate (CHO) during exercise to meet the demand for ATP. Factors including exercise intensity/duration and fitness level are recognized as primary determinants of the relative contribution of these macronutrients to substrate metabolism, although exercise mode has also been identified. The aim of this study was to determine potential differences in substrate metabolism during treadmill (TM) and cycle ergometer (CE) exercise performed at equal rating of perceived exertion (RPE). METHODS: Eleven recreationally active women (age =23.0±3.0 yr, Body Mass Index =20.7±1.7 kg/m2) performed one 30 min bout of endurance exercise on the CE and TM separated by 1 wk. Three 10 min stages of exercise were completed at RPE equal to 11, 13, and 15. During exercise, gas exchange data were continuously obtained to determine fat and CHO oxidation. Subjects fasted 3 h prior to exercise and standardized their dietary intake 48 h prior to each bout. Two-way ANOVA with repeated measures was used to determine differences in respiratory exchange ratio (RER) and fat and CHO oxidation between exercise modes. RESULTS: RER was higher (P<0.05) during CE compared to TM at RPE equal to 11 (0.92±0.03 vs. 0.87±0.06), 13 (0.95±0.03 vs. 0.89±0.05), and 15 (1.00±0.03 vs. 0.93±0.04), leading to lower fat oxidation (P=0.009) and higher CHO oxidation in response to TM versus CE (P=0.003). CONCLUSIONS: Greater fat utilization occurred in response to treadmill walking at RPE ranging from 11-15 versus cycle ergometry.

Attenuated RPE and leg pain in response to short-term high-intensity interval training.

This study examined the effect of 6 days of high intensity interval training (HIT) on rating of perceived exertion (RPE) and leg pain. Eleven men (age and VO(2)max=25.3±5.5 year and 45.6± mL/kg/min) and 9 women (age and VO(2)max=25.2±3.1 year and 41.1±6.1 mL/kg/min) with similar activity level and VO(2)max underwent HIT consisting of repeated Wingate tests separated by 5 min recovery over a 2-3 week period. Five men and four women served as controls and did not perform HIT. Four minutes after each bout across all days of training, RPE and leg pain were recorded using categorical scales. Repeated measure ANOVA was used to assess differences in RPE and leg pain in response to acute bouts and days of HIT. Data revealed that RPE and pain increased (p<0.05) after bout 1 to after bout 4. Compared to day 1 (6.3±1.9), RPE after bout 4 (5.0±1.4) decreased (p=0.001) in response to 6d of HIT. Training significantly reduced (p<0.05) leg pain, as pain declined from day 1 (6.20±2.29) of HIT versus day 6 (5.20±2.04). Data show that RPE and leg pain are significantly attenuated by 6 d of HIT, which is likely due to the physiological adaptations accrued in response to this modality of training.

Adaptations to high-intensity training are independent of gender.

The purpose of this study was to identify potential gender discrepancies in adaptation to low-volume high-intensity interval training (HIT). Active, young men (n = 11, age = 25.3 ± 5.5 years) and women (n = 9, age = 25.2 ± 3.1 years) matched for age, physical activity, and VO(2max) completed six sessions of HIT separated by 48 h over a 2-3 week period. Subjects completed four Wingate tests on days 1 and 2, five on days 3 and 4, and six on days 5 and 6. A control group of five men and four women (age = 22.8 ± 2.8 years) completed all testing, but did not perform HIT. Changes in VO(2max), oxygen (O(2)) pulse, peak/mean power output, fatiguability, substrate oxidation, and voluntary force production of the knee flexors and extensors were examined pre- and post-training with repeated measures ANOVA, with gender and group as between-subjects variables. Results showed significant (p < 0.05) improvements in VCO(2max) and peak/mean power output in response to HIT, as well as reduced respiratory exchange ratio and heart rate during submaximal exercise. The magnitude of change in VO(2max) (5.9 vs. 6.8%), power output (10.4-14.9% vs. 9.1-10.9%), and substrate oxidation was similar (p > 0.05) between men and women. Data show that adaptations to 6 days of low-volume HIT are similar in men and women matched for VO(2max) and physical activity.