6 Weeks of Cycling BFR, Outcomes

It's been about 6 weeks since I began the "cycling with BFR" project, and it's time for outcome measurements. In this post we will cover the training regime that was performed, SmO2/HR/DFA a1 monitoring during the sessions and what performance improvements were seen. However, before doing a pre/post comparison, I would like to backtrack a bit to about 10 months ago to elaborate on why BFR training in my specific circumstance has been helpful. At that time, my usual training schedule consisted of a polarized program where on Monday and Friday I would do 30 sec max Wingates x 2-3 and a 5 minute near max constant intensity interval (the rest of the week would be all zone 1 = moderate domain intensity). Unfortunately, during Early 2025, I noted a 30-second run of ventricular tachycardia. After a negative cardiac evaluation, it was thought to be related to overreaching/autonomic imbalance. We decided to just observe the rhythm (simple to do since I'm tracking ECG anyway) and I backed off on the Monday HIT to keep it as zone 1 only. Over the past several months or so I saw a modest drop in my LT1/2 and maximum 5 minute power. This is important to note as I'll come back to the benefits of BFR training to those who can't train maximally, either over a short or long term period. So, a typical scenario for a 69-year-old with either an injury or inability to perform HIT several times a week, seeking to boost their fitness.

Methods employed:

• Either Polar H10, Movesense Medical ECG or Faros 180 ECG for DFA a1/HR (depending on the day tested)
• BSX and Moxy SmO2 monitors, either on the rectus femoris or calf 
• Saga Cuffs on the legs - estimated LOP (limb occlusion pressure) 180 mmHg. Initial working pressure was 60% LOP, increasing to 74% over the 6 weeks. This is "new" from my last post. I noted improved tolerance of the applied pressure over time, and was able to gradually raise pressure without worsening pain. 

Exercise Intervention protocol:

• Warm up for 20 minutes. 
• Monday: 6 sets of 2 minute occlusions while cycling at near LT1 power, with a deflation for 2 minutes cycling at 40 watts below LT1. Total time of BFR on/off = 24 minutes (6 sets x 4 min).
• Friday, same as above, but added a 5 minute near max constant power interval 20 minutes after the warmup but before the 6x BFR.

Results:

Wingate 30 sec and 5 minute power: 

 

• The above represents the "best" interval of the month, over the past year. Interestingly, it took about 2 months for the "HIT detraining" to affect my stats. But when it did, the results were pretty clear. I was aware of this but chalked it up to getting older and training with less intensity. Incidentally, the total joules per week were the same pre/post.
• As we can see the BFR (arrow from October to November) appears to have brought me at least partially back to where I was, but it is based on only one session last week. Could it be a fluke? Let's go next to the lactate testing for confirmation.

Lactate testing:

Methods: Many have written to me regarding how I do La testing. Considering my reluctance to do a classic MLSS or even an incremental ramp to failure, I have come up with what I consider an accurate estimate of LT1 and a ballpark of LT2. Essentially, what I do is a series of 5 minute constant power intervals just under and over my guesstimate of LT1 and look for the initial rise above baseline (about 0.5 mmol/L). All testing was done with 2 samples, back to back, and averaged. Here are the LT1 numbers in relation to the above power figures:

Watts	25-Jun	25-Aug	25-Nov
0	1.25	1.5	1.7
150	1.2
170	1.45	1.6	1.6
180	1.65	2.1	1.85
190	1.7		2
200	2.3
210		3

 

• Results: It seems like the LT1 rose about 10 watts after BFR and perhaps halfway back to where it was a year ago, about 200w.

For LT2, I use the 3-minute submaximal method originated here:

 

 

	25-Feb	25-Aug	25-Nov
MLSS calc (W)	250	228	237

• It looks like about a 10-watt boost from pre BFR.

Summary so far:

Six weeks of BFR yielding: 

• About 5% rise in Wingate 30 and 5 minute constant intensity power
• Ten watt rise in LT1 and LT2, equates to a ballpark 5% improvement.

How does this compare to prior studies? 

This is very difficult to say since the protocols are all over the place with little consistency in LOP, compression time, intensity, etc. However, the following table is from a recent review, and as you can see, my results are somewhat in line with the various reports:

Besides the obvious benefits of BFR training during and/or post injury, older athletes in particular may mitigate the loss of VO2max and performance seen with aging. This post coincided with the publication of an interesting paper analyzing factors responsible for the age related decline in VO2max.

 

Since BFR has been shown to improve all of the above "subsystems" mentioned, it may be even more beneficial for the aging athlete than attempting HIT on a regular basis. Since I began BFR, I have ceased Wingate 30s intervals altogether, yet my recent attempt still showed a 5% improvement in power.

For a quick peek at another individual, here is a recent SmO2, HR and DFA a1 profile seen during my wife's 6 set BFR series (85% LOP, low zone 1 power - 35 watts, 2 min compressions/2 minute deflations pedaling). Taken from Runalyze:

 

DFA a1 in red circles (Kubios/H10) 

 

• Measured lactate was 4.2 mmol/L at the end of the 6th interval. 
• This is notable as she has a torn knee meniscus and hasn't been able to approach zone 3/severe intensity for many years.

Final thoughts:

• BFR training is quite readily achievable with commercial cuffs, SmO2, HR and DFA a1 monitoring. 
• There are many permutations that can be done, but I have provided some advice with short-term outcomes for the reasonable protocol employed here.
• From my viewpoint, it is most appropriate for those with injuries or orthopedic issues that preclude HIT/SIT on a regular basis. It may also be particularly appropriate for the aging athlete since it addresses the local circulatory, muscular, and metabolic factors that degrade with age.
• My plan is to continue this for another 6 weeks with repeat testing.
• Incidentally, even with the added "stress" of BFR, I have not seen any uptick in arrhythmia (APC or VPC). 

• BFR intro and monitoring DFA a1, SmO2

  BFR in cycling II

 

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