Tee’d up for this round of the Owens Recovery Science blog we have a topic we’ve never covered before: Upper extremity cycle ergometry. That’s due in large part to the fact that there aren’t many studies at all. I think this topic is interesting because it starts to expose some of the limitations of the existing literature on blood flow restriction training and why it’s imperative that practitioners not only possess, but apply a basic understanding of exercise principles when using BFR.
The study titled, “Acute physiological responses to steady‑state arm cycling ergometry with and without blood flow restriction” comes out of Dr. Summer Cook’s lab at University of New Hampshire, but is a collaboration with another long-time BFR researcher, Dr. Brendan Scott from Murdoch University.(Frechette et al., 2023) They utilized a randomized cross-over design with four different conditions to examine UE cycle ergometry combined with BFR. The conditions were as follows:
HW - Steady state cycling at 60% of an individual’s max power output
LW - Steady state cycling at 30% of max power output
LW + BFR - Steady state cycling at 30% max with BFR @ 70% LOP
BFR only - BFR at 70% of LOP
During each condition they captured the following physiologic data:
Heart Rate (HR)
VO2 Peak (VO2)
Blood Lactate (BL)
Rating of Perceived Exertion (RPE)
Borg 6-20 scale (during)
Local UE rating q 2 minutes
Whole body rating q 2 minutes
RPE 1-10 scale (session)
Upon completion of session
Upon each visit to the lab individuals cycled and/or had BFR applied continuously for 15 minutes at the above described workloads and pressures. I suspect many of you after seeing the study design have some thoughts in terms of what they will find. You might also have some questions regarding the choice of 70% LOP as the pressure used. Following I’ll share my initial thoughts and then my thoughts after having time to ponder a bit.
Why'd they choose that pressure?
The pressure choice definitely puzzled me, and the authors did not provide much rationale for their selection. I expected they’d use pressures more in-line with the methodology paper that Dr. Scott was a contributing author to, but then I recalled, that paper didn’t differentiate between upper and lower extremity recommendations. (Patterson et al., 2019) It merely suggested that individualized pressures be used and a range of 40-80% of LOP be utilized.
We typically recommend 40-50% LOP for UE exercise which we base off a study out of Dr. Jeremy Loenneke’s lab that indicated 40% LOP was just as effective as 90% blood-flow restriction. (Counts et al., 2016) They examined different pressures in 10% increments with 40 and 90 being the lower and upper bounds. Then of course there’s the more recent paper out of Houston Methodist indicating 50% LOP is the optimal pressure for shoulder exercise. (Roehl et al., 2023) Up until this study no one had even used an individualized pressure in an upper extremity cycling task, so it seemed logical to me they’d target a lower magnitude pressure much like has been used in resistance exercise trials. But, as I read the introduction to this paper it pointed me to a potential reason for their use of a higher pressure. The authors first note that “physiological responses to exercise may differ between the arms and legs.” Specifically, “...larger increases in blood flow can be expected in the arms…due to lower oxygen extraction in the muscles of the arms.” They also cite three recent studies examining blood volume responses to BFR upper and lower body cycling which “...increases…with the arms being more responsive than the legs…” The final piece here I think is the fact that it has previously been shown that higher pressures in the UE’s (80% LOP) elicit greater vascular conductance than lower pressures (40% LOP). (Mouser et al., 2019) So given the ultimate goal of their study was to evaluate how submaximal upper extremity cycle ergometry may “augment acute physiological and perceptual responses which underpin improvements in fitness, and how these demands compare to traditional higher-workload exercise”, the choice of a higher pressure makes some sense given our existing knowledge.
What did they find?
The authors hypothesized “that BFR alone would be insufficient to augment these physiological and perceptual measures, whilst adding BFR to low-workload arm cycling would exaggerate the demands of exercise, though not to the same level as performing high-workload exercise.” Upon reading the methods that hypothesis sounded likely to be true. It’s essentially what we seem to know about blood flow restricted exercise on the whole; the addition of BFR will make low load resistance training more intense and fatiguing than the low intensity exercise without BFR. Interestingly, what the authors found was that both heart rate (HR) and blood lactate (BL) responses to the 30% workload were unchanged by the addition of BFR for the duration of the exercise. A surprising finding no doubt, but made more puzzling by the fact that “sessional RPE’s were similar between the HW and LW-BFR conditions and greater than the LW condition.” Thus, the efficacy of adding BFR during low-workload UE aerobic exercise is questionable since it also “may not be well-tolerated by some participants.”
HW (60% max)
LW (30% max)
LW+BFR (70% LOP)
BFR (70% LOP)
← 68% →
← 41% →
* 7.7 mmol/L
← 3.5 mmol/L →
RPE (q 2mins)
← 10.4 →
* denotes significantly different from all other conditions
BFR Training Knowledge Gaps (not a comprehensive assessment by any standard)
I said earlier that I think this topic is interesting because it starts to expose some of the limitations of the existing literature on BFR. While UE cycling might be a less common task to add BFR to, this study helps us illustrate that merely adding the BFR cuff to a task doesn’t mean that something positive for muscle is happening. For example, this study should cast serious doubts on the claims we hear from time to time that BFR is all systemic and the addition of UE BFR will somehow prevent LE atrophy <eye roll>. Elaborating on this notion a bit, consider if you will that the vast majority of resistance training with blood flow restriction studies have been conducted on the quadriceps or the biceps. Very few studies have even looked at the hamstrings, and I believe one has looked at the triceps. None of those studies were constructed in a way to elucidate optimal parameters for exercise with blood flow restriction in those muscle groups. This makes the hamstring study out of USC even more valuable since subjects required only 30% 1RM eccentrically with BFR at 80% LOP to achieve similar increases in force production to a heavy loaded cohort. (Jones et al., n.d.) The authors note in their discussion that there exist known differences in how UE’s and LE’s respond to exercise. Specifically they note, “It is possible that lower amounts of muscle mass, differences in type 2 muscle fiber distribution, diminished oxygen extraction possibly due to vascular properties, and heightened sensitivity/responsiveness to oxygenation in the upper limbs compared to the lower limbs, could result in divergent physiological responses during upper limb BFR aerobic exercise.” Collectively this highlights for me how important it is that we individualize load and pressure according to the parameters set forth by the Patterson methodology paper. Further, it illustrates that in order to ensure the effectiveness of our exercise prescription we must monitor effort and routinely re-assess our client’s strength so that modifications can be made in a timely fashion.
Should you use blood flow restriction training with UE cycle ergometry?
One final piece here, as you might be thinking, UE cycling with BFR lacks value given the fact it did not augment cardiorespiratory or metabolic responses. It’s important to note that the perceptual demands of the LW+BFR were greater than LW. This could of course be merely a rating of the pressure as the authors note, but it could also be something different. If perceptual demands are in fact augmented, then there’s potential to improve some fatigue resistance which of course could have value for overhead athletes and some clinical populations. Further, this was an acute study on healthy people, clinical populations certainly could respond differently; it’s harder though to reason how repeated exposures might elicit something different physiologically.
Have you tried UE cycling ergometry with BFR in your practice? What successes, or lack thereof, have you had? Let us know!!
Counts, B. R., Dankel, S. J., Barnett, B. E., Kim, D., Mouser, J. G., Allen, K. M., Thiebaud, R. S., Abe, T., Bemben, M. G., & Loenneke, J. P. (2016). Influence of relative blood flow restriction pressure on muscle activation and muscle adaptation. Muscle & Nerve, 53(3), 438–445.
Frechette, M. L., Scott, B. R., Vallence, A.-M., & Cook, S. B. (2023). Acute physiological responses to steady-state arm cycling ergometry with and without blood flow restriction. European Journal of Applied Physiology, 123(4), 901–909.
Jones, M. J., Dominguez, J. F., Macatugal, C., Coleman, K., Reed, B., & Schroeder, E. T. (n.d.). Low Load With BFR vs. High Load Without BFR Eccentric Hamstring Training Have Similar Outcomes on Muscle Adaptation. Journal of Strength and Conditioning Research / National Strength & Conditioning Association. http://journals.lww.com/nsca-jscr
Mouser, J. G., Mattocks, K. T., Buckner, S. L., Dankel, S. J., Jessee, M. B., Bell, Z. W., Abe, T., Bentley, J. P., & Loenneke, J. P. (2019). High-pressure blood flow restriction with very low load resistance training results in peripheral vascular adaptations similar to heavy resistance training. Physiological Measurement. https://doi.org/10.1088/1361-6579/ab0d2a
Patterson, S. D., Hughes, L., Warmington, S., Burr, J., Scott, B. R., Owens, J., Abe, T., Nielsen, J. L., Libardi, C. A., Laurentino, G., Neto, G. R., Brandner, C., Martin-Hernandez, J., & Loenneke, J. (2019). Blood Flow Restriction Exercise Position Stand: Considerations of Methodology, Application, and Safety. Frontiers in Physiology, 10, 533.
Roehl, T., Lambert, B. S., Ankersen, J., Hernandez, K., McCulloch, P. C., & Hedt, C. (2023). Optimal Blood Flow Restriction Occlusion Pressure for Shoulder Muscle Recruitment With Upper Extremity Exercise. The American Journal of Sports Medicine, 3635465231166959.