Mikel Egaña

Mikel Egaña

Associate Professor of Physiology at Trinity College Dublin

Location Watts Building, Trinity College Dublin


  • thank you for the relevant comments. I agree with Geraldine's interpretation.

  • Thank you for the comment Susan. It is unclear why the reduction in VO2 kinetics is not apparent in 'older' (60-70 yr old) participants even if they still show significant reductions in maximum exercise capacity or VO2max compared with their non-diabetic peers.
    It is possible that the T2D-induced slowing in VO2 kinetics during moderate exercise might reach a...

  • Yes, often the blood flow and oxygen uptake stabilise at a similar level in T2D and healthy controls, however, the slower rates of increase in VO2/blood flow observed in people with T2D are linked to earlier onset of fatigue and harder perception of even light/moderate everyday life efforts such us climbing stairs etc.

  • Hi Nicola, sure it does. However, when you compare exercise tolerance in an overweight/obese group with 'uncomplicated' T2D with a non-diabetic healthy group with the same body mass index (i.e. same level of overweightness/obesity) the group with T2D show significantly lower exercise tolerance.

  • Thanks for the link and useful tips Alexander

  • yes, very valuable comments. Thanks for sharing them.

  • Hi Eli, tobacco is probably the primary factor (see also the list on the right side of the diagram). A combination of these factors then lead to COPD and consequently to a respiratory and leg muscle dysfunction.

  • I agree with you comment, Ruth, thanks.

  • Many thanks for all your contributions so far. I really enjoyed reading your experiences and the way you would prescribe exercise. Overall they make a lot of sense.

  • It appears that yes, at least adolescents with T1D also show cardiovascular abnormalities and lower exercise tolerance.

  • good point Sarah. Difficult to know but I think it can go both ways...

  • Hi Sherraine,
    The mean disease duration (from diagnosis) was on average 5 years (range 0 to 10 years) in this cohort.

  • Sally, the rapid decline or 'decay' actually happens at around 20 sec (not min). This observation is quite consistent in most people, but the reason is not well understood. It can be due to a reduction in the effectiveness of vasodilators underlying the initial fast 'growth' phase, but more research is needed to understand the causes.

  • Thanks you for the valuable comment Michael.

  • Great to hear you are observing such positive benefits with your patients Gary. Thanks for sharing your experiences.

  • Thanks for the relevant comment, Gillian. As katharine mentions, they do it up to their ability level (which is relatively low in absolute terms). It might sound surprising but there is evidence showing that people with severe COPD can only last continuous exercise (50 to 80% peak maximal capacity) for 5-12 minutes, whereas they can sustain interval exercise...

  • This is interesting, John. Thanks for sharing.

  • Katherine,
    The ventilatory threshold (which is a very relevant non-invasive threshold to accurately prescribe exercise) is often linked (and often coincides with) lactate threshold, given that the higher acid concentration induced by the production of lactate affects/induces a disproportionate increase in minute ventilation (i.e.above the ventilatory...

  • Thanks for your comment, Michelle. I am not aware of any studies showing whether HIT is sustainable unsupervised in T2D (we are actually investigating this currently!). Your approach sounds appropriate.

  • This is a good point Christine. In studies that include an 'unsupervised' exercise training phase researchers often have weekly telephone conversations with participants to check how are they getting on etc., and participants are re-tested in the exercise laboratory at the end of the program. The results obtained during the laboratory test are very useful to...

  • I agree, David. The social aspect is also critical for long term exercise adherence.

  • Sounds like an appropriate approach, Chigozirim.

  • Very true. They should control/monitor their blood glucose levels before and after exercise.

  • Very good comment, Melanie. Indeed it is very important to have as much contact as possible with clients.

  • Good point Barry. This is because ageing 'per se' slows the VO2 kinetics response, and diabetes doesn't magnify this slowing response in older people as it does in younger-middle age adults. However, note that maximal exercise is still significantly reduced in older people with type 2 diabetes compared with healthy non-diabetic older people. Research exploring...

  • Cheryl,
    It appears that a combined program including both aerobic and resistance exercise is best to improve insulin sensitivity (this is mentioned in the next step).

  • Exactly John!

  • Very good comment, Stuart. Yes, during moderate submaximal exercise pulmonary O2 uptake and blood flow do increase to a steady state; however, during heavy/maximal exercise both, O2 uptake and peak blood flow responses are significantly reduced.

  • Thanks for the comment Joanne. There are a number of mechanisms affecting them. For a comprehensive contemporary review, perhaps check the following paper (free to download):
    Green S, Egana M, Baldi JC, Lamberts R, and Regensteiner JG. Cardiovascular control during exercise in type 2 diabetes mellitus. J Diabetes Res 2015: 654204, 2015.