A long-standing assumption in evolutionary biology is that the evolution rate of protein-coding genes depends, largely, on specific constraints that affect the function of the given protein. However, recent research in evolutionary systems biology revealed unexpected, significant correlations between evolution rate and characteristics of genes or proteins that are not directly related to specific protein functions, such as expression level and protein–protein interactions. The strongest connections were consistently detected between protein sequence evolution rate and the expression level of the respective gene. A recent genome-wide proteomic study revealed an extremely strong correlation between the abundances of orthologous proteins in distantly related animals, the nematode Caenorhabditis elegans and the fruit fly Drosophila melanogaster. We used the extensive protein abundance data from this study along with short-term evolutionary rates (ERs) of orthologous genes in nematodes and flies to estimate the relative contributions of structural–functional constraints and the translation rate to the evolution rate of protein-coding genes. Together the intrinsic constraints and translation rate account for approximately 50% of the variance of the ERs. The contribution of constraints is estimated to be 3- to 5-fold greater than the contribution of translation rate.
The use of continuous glucose monitors (CGMs) in individuals living without diabetes is increasing. The purpose of this study was to profile various CGM metrics around nutritional intake, sleep and exercise in a large cohort of physically active men and women living without any known metabolic disease diagnosis to better understand the normative glycemic response to these common stimuli. A total of 12,504 physically active adults (age 40 ± 11 years, BMI 23.8 ± 3.6 kg/m2; 23% self-identified as women) wore a real-time CGM (Abbott Libre Sense Sport Glucose Biosensor, Abbott, USA) and used a smartphone application (Supersapiens Inc., Atlanta, GA, USA) to log meals, sleep and exercise activities. A total of >1 M exercise events and 274,344 meal events were analyzed. A majority of participants (85%) presented an overall (24 h) average glucose profile between 90 and 110 mg/dL, with the highest glucose levels associated with meals and exercise and the lowest glucose levels associated with sleep. Men had higher mean 24 h glucose levels than women (24 h—men: 100 ± 11 mg/dL, women: 96 ± 10 mg/dL). During exercise, the % time above >140 mg/dL was 10.3 ± 16.7%, while the % time <70 mg/dL was 11.9 ± 11.6%, with the remaining % within the so-called glycemic tight target range (70–140 mg/dL). Average glycemia was also lower for females during exercise and sleep events (p < 0.001). Overall, we see small differences in glucose trends during activity and sleep in females as compared to males and higher levels of both TAR and TBR when these active individuals are undertaking or competing in endurance exercise training and/or competitive events.
7 December 2023 in Biomedical Signal Processing and Control
Background: This descriptive observational study reports on continuous glucose monitoring (CGM) data, using a novel glucose biosensor (Abbott Libre Sense Glucose Sport Biosensor), during professional game play and during daily life in elite European football players. Methods: Eighteen healthy male elite football players (age: 27.5 ± 5.1 years; height 180.1 ± 7.2 cm, weight 74.2 ± 9.1 kg, UEFA Champions League club) participated, with a subset examined for a single game for active (n = 10) and reserve (n = 4) players. Group comparisons used unpaired t -tests or Wilcoxon rank-sum tests; within-group differences used repeated measures one-way analysis of variance or Friedman test. Descriptive statistics were summarized for 24-hour data for daytime (06:00 am -10:59 pm ) and nighttime (11:00 pm -05:59 am ). Results: Higher mean CGM glucose was observed during-game in active compared with reserve players (159 ± 23 vs 133 ± 25 mg/dL, P = .09), with significantly higher time above range (TAR, 72.8 ± 32.02 vs 29.7 ± 37.9%, P = .04) and lower time in range (TIR, 26.7 ± 31.9 vs 70.3 ± 37.9%, P = .04). In the 90 minute pre- to 180 minute post-game period, TAR (57.3 ± 26.6% vs 16.1 ± 20.2%, P = .02) and mean iG (149 ± 19 vs 123 ± 14 mg/dL, P = .02) remained higher for active players. For all 18 players, TIR was 89.4 ± 11.7 and 91.6 ± 13.7%, TAR was 5.9 ± 6.7 and 2.9 ± 5.7%, and time below range was 4.5 ± 10.5 and 5.3 ± 13.2% for day and night, respectively. Conclusions: This observational study suggests that elite European footballers may have significant increases in glycemia, as measured by CGM, supporting the notion that mild hyperglycemia can occur during and after active competition in healthy and metabolically normal athletes, perhaps because of competition stress.
Glucose data regarding extreme elite performances in athletes without diabetes remains limited. The purpose is to characterize continuous glucose monitoring (CGM) responses in elite athletes across distinct high-performance contexts. This descriptive case series includes three separate elite athletes who used a CGM during their respective sporting events. The first is an ultra-endurance relay cycling world-record performance (Race Across the West, RAW), the second is a continuous high-intensity Everesting Challenge cycling record attempt, and the third is a maximal constant-weight no-fins breath-hold depth dive performed in international competition. Glycemic outcomes, as measured by CGM, included mean, maximum, and minimum glucose, glucose standard deviation (SD), and the percentage of time in tight glucose range (TITR: 70–140 mg/dL; 3.9–7.8 mmol/L), time below range (TBR: <70 mg/dL; 140 mg/dL; >7.8 mmol/L). Other performance data, including peak power, heart rate, and lactate, are also provided where available. During the RAW challenge lasting 44 h and 20 min, mean glucose was 91 ± 23.2 mg/dL (mean ± SD) with 9.15% TBR and 35.58% TITR during cycling and 115 ± 24.7 mg/dL with 9.11% TBR and 43.16% TITR during resting periods. In contrast, the Everesting Challenge cycling record attempt demonstrated a persistently elevated glucose profile (160 ± 5.7 mg/dL), minimal variability (CV 3.5%), and 100% TAR140. Following the maximal breath-hold depth dive, interstitial glucose was 100% TAR140 during recovery (187 ± 18.5 mg/dL), alongside marked elevations in blood lactate concentrations (peak 13.4 mmol/L). The series of case studies demonstrate that substantial deviations from traditional euglycemic ranges are common during elite performance in athletes without diabetes. Interpretation of CGM data in athletic settings should therefore be performance- and context-specific rather than based on clinical glycemic thresholds.
3 March 2026 in Journal of Diabetes Science and Technology
Background: To describe changes in continuous glucose monitoring (CGM)-derived glucose metrics of healthy and physically active participants with mild dysglycemia at baseline (>5% time with glucose levels outside of 70-140 mg/dL) who wore a real-time CGM device (GSB, Glucose Sport Biosensor) integrated with a smartphone mobile application over an eight-week period (four GSB wear periods). Methods: Two hundred twenty-five participants (51 females and 174 males) aged 45.0 ± 10.1 years with body mass index 23.4 ± 3.9 kg/m 2 with suboptimal time in tight range (TITR) (ie, <95%) wore a GSB for approximately eight weeks. Linear mixed-effects models (LMEMs) were used to compare the cumulative time in different glycemic zones (% time below range [TBR, 140 mg/dL]) with respect to each GSB wear time. Results: Linear-mixed effects model analysis returned significant effects of sensor on TITR and TBR across four wear periods (both P < .001), with inter-individual variability in baseline values and response slopes. Each day of sensor wear increased TITR by 0.59% (95% confidence interval [CI]: 0.50, 0.69, P < 0.001) and reduced TBR (−0.42 %, 95% CI: −0.50, −0.35, P <.001) and TAR (−0.17 %, 95% CI: −0.24, −0.10, P < .001), with small sensor-dependent differences in daily improvements. Conclusions: These findings indicate both cumulative and day-to-day gains in glucose control with repeated sensor use for individuals with a TITR <95%. Indeed, CGM use coincided with short-term improvements in glucose metrics. Future studies should directly measure lifestyle behaviors to determine which factors may contribute to improvements in glycemia.