lessons learned from Para cyclists

Steady Glucose Monitoring (CGM) is gaining consideration as a device for optimising dietary counselling in athletes. By offering real-time glucose knowledge, CGMs supply the potential to reinforce our understanding of how athletes’ our bodies reply to coaching, restoration, and diet. In our research, revealed within the European Journal of Sport Science, we investigated the usage of CGMs in Para athletes to discover their potential functions and limitations.

In our research (1), we adopted 13 elite Para cyclists, together with each hand bikers and standard cyclists, for 2 weeks. Individuals wore CGMs on the again of the higher arm and logged meals and coaching classes. We in contrast CGM knowledge with glucose readings taken from finger-prick blood samples to guage the accuracy of CGMs throughout relaxation and train.

Our purpose was to uncover glucose profiles in Para cyclists and decide the accuracy of CGMs below completely different circumstances. We targeted on quite a few key questions:

1. To what extent fluctuate glucose concentrations all through the day and evening, and are there any indicators of disturbed glucose regulation?

2. Is CGM as correct throughout train as it’s at relaxation?

3. And what sensible concerns ought to practitioners take into accout when utilizing CGMs with (Para) athletes?

We discovered that Para cyclists spent 91% of their time within the wholesome glucose vary (3.9–7.8 mmol/L). Delicate hyperglycemia (≥7.8 mmol/L) was generally noticed after meals, significantly following lunch. Extreme hyperglycemia (≥10 mmol/L), as ceaselessly seen in people with diabetes, was practically absent on this inhabitants. These findings recommend that Para cyclists usually preserve well-regulated glucose ranges. Athletes with spinal twine accidents (SCI) appeared to have a better danger of nocturnal hypoglycemia (<3.9 mmol/L). Notably, one SCI athlete spent a median of 36% of the evening in a hypoglycemic state. Nocturnal hypoglycemia has the potential to impair sleep high quality (2) and has been proven to trigger next-day fatigue in people with diabetes (3). Whereas these results weren’t examined within the present research, they current an intriguing space for future analysis, significantly concerning their impression on restoration and efficiency in SCI athletes.

Accuracy is assessed by calculating the distinction between the CGM and the finger prick blood glucose values and changing it right into a proportion. A distinction of 10% is taken into account correct and between 10-20% is taken into account acceptable. CGM accuracy was acceptable at relaxation (12%) however declined significantly throughout train (34%). The discrepancy was bigger for hand bikers (41%) in contrast with standard cyclists (24%), probably as a result of the sensors had been positioned on the higher arm, which is close to energetic arm muscle mass in hand bikers. This discount in accuracy primarily mirrored an overestimation of CGM-derived glucose concentrations in contrast with capillary blood glucose.

Throughout train, a number of physiological elements can impair the accuracy of steady glucose monitoring. CGM sensors measure glucose within the interstitial fluid however are calibrated to mirror blood glucose concentrations. Underneath resting circumstances, this calibration is dependable as a result of interstitial and blood glucose ranges are carefully correlated. Nonetheless, throughout train, elevated blood stream and glucose uptake by energetic muscle mass can disrupt this relationship (4), resulting in much less correct CGM readings. Moreover, exercise-induced modifications in physique temperature and pH might alter the enzymatic exercise of the glucose sensor, additional amplifying measurement errors. These results are probably extra pronounced close to energetic muscle mass, which may clarify the larger measurement errors noticed in hand bikers in comparison with standard cyclists (see weblog Are continuous glucose monitors (CGMs) accurate?).

CGMs present useful insights into glucose profiles, doubtlessly supporting superior feeding methods round coaching. Nonetheless, glucose fluctuations, similar to delicate post-meal hyperglycemia, are a traditional physiological response to eating regimen, train, and stress. In athletes, these fluctuations could also be extra pronounced as a result of greater carbohydrate and vitality consumption wanted to assist coaching calls for. Such variations shouldn’t be misinterpreted as impaired glucose regulation or intolerance. Whereas CGMs can help in refining diet methods, overinterpretation of knowledge with pointless dietary modifications ought to be prevented (see blogs CGM in sport and How can CGM be used?).

The upper danger of nocturnal hypoglycemia in SCI athletes warrants consideration. Analysis ought to discover its impression on sleep and efficiency, whereas dietary changes, similar to night meal composition, might assist mitigate these episodes.

Practitioners utilizing CGMs with athletes ought to pay attention to their limitations throughout train. CGMs are likely to overestimate glucose concentrations in comparison with capillary blood glucose, significantly when the sensor is positioned close to energetic muscle mass. Cautious consideration of sensor placement website and cautious interpretation of train knowledge are important to keep away from misinformed selections.

Our just lately revealed research offers useful insights into the applying of CGM in Para cyclists, who usually display well-regulated glucose concentrations with out proof of impaired glucose tolerance. Nonetheless, the elevated danger of nocturnal hypoglycaemia in athletes with spinal twine accidents warrants consideration, significantly concerning its potential results on sleep high quality, fatigue, and long-term well being.

Whereas CGMs supply important potential for analysing glucose dynamics in response to meals consumption and train, their sensible use in athletic populations requires cautious consideration as a result of elements similar to exercise-induced inaccuracies, overinterpretation of knowledge, and the necessity to stability insights with established dietary tips. This research underscores the significance of critically evaluating rising instruments like CGMs to make sure they’re utilized successfully to optimize well being and efficiency.

1. Weijer, V., Van Der Werf, R., Van Der Haijden, M., Jeukendrup, A., Van Loon, L. J. C. and Dijk, J. V. (2024) ‘Steady glucose monitoring in para cyclists: An observational research’, Eur J Sport Sci, 24(12): 1809-1819.

2. Banarer, S. and Cryer, P. E. (2003) ‘Sleep-related hypoglycemia-associated autonomic failure in kind 1 diabetes: lowered awakening from sleep throughout hypoglycemia’, Diabetes, 52(5): 1195-1203.

3. King, P., Kong, M.-F., Parkin, H., Macdonald, I. A. and Tattersall, R. B. (1998) ‘Properly-Being, Cerebral Perform, and Bodily Fatigue After Nocturnal Hypoglycemia in IDDM’, Diabetes Care, 21(3): 341-345.

4. Moser, O., Yardley, J. E. and Bracken, R. M. (2018) ‘Interstitial Glucose and Bodily Train in Sort 1 Diabetes: Integrative Physiology, Expertise, and the Hole In-Between’, Vitamins, 10(1): 93.