Calculate Pressure | Aerobic Fitness | One Repetition Maximum – See more
Calculate Pressure & LOP Explained – Read more
When Limb Occlusion Pressure (LOP) is not accessible, we recommend the Calculate Pressure module.
We have developed and updated the algorithm from the comprehensive science and data in the predictors of Limb Occlusion Pressure (LOP) i.e., Arterial Occlusion Pressure (AOP) for You to enjoy Effective, Save and Convenient BFR Training. When choosing “Calculate Pressure”, remember to measure the circumference of your thigh or upper arm in a relaxed state before exercising.
When operating this module, different characteristics are needed for the algorithm to calculate an indicative-individual-pressure (mmHg) such as limb circumference, age, gender, body compositions, training condition and previous experience with blood flow restriction training.
We do not recommend to use arbitrary pressures, even though, 80 mmHg and 100 mmHg for the upper and lower body, respectively, would be applicable for about 90% of all people. Though, due to inter-individual anthropometric and physiological differences, especially limb circumference, sub-cutaneous fat, and arterial blood pressure, a default pressure may not restrict blood flow to the same degree in different individuals.
Nerd Alert – How & Why the Module Works
The aim of the algorithm are to predict the pressure in the commonly recommended zone or “sweet-spot” of 40-70% and 50-80% LOP for the upper and lower body, respectively. Currently, the algorithm can predict this recommended pressure for +95% of all people. From the comprehensive research and data, it seems that limb circumference can explain about 50-70% of the inter-individual variability in LOP when the same cuffs are being applied. Though, thigh circumference is the biggest anthropometric predictor of LOP, it seems that other factors are also of importance. From the large amount of data and research, it seems that both gender, age and body composition influence LOP and the relative amount of blood flow that is restricted at sub LOP pressures. That is why these predictors are included in the algorithm, along with “training condition”, as we find this of particular importance for Ratings of Perceived Exertion (RPE). But actually, the width of the cuff is the most important factor to consider, for effective and safe prescriptions of BFR pressures (mmHg). So, please mind that the “Calculate Pressure” module is only applicable for Fit Cuffs® product selection.
“In addition, we have outlined models which indicate that restrictive cuff pressures should be largely based on thigh circumference and not on pressures previously used in the literature.” (Loenneke et al. 2012).
Limb occlusion pressure (LOP) versus the ratio of tourniquet cuff width to limb circumference. For any given limb circumference, the tourniquet pressure required to stop arterial blood flow decreases inversely as the width of the tourniquet cuff increases. (Reproduced, with modification,from: Graham B, Breault MJ, McEwen JA, McGraw RW. Occlusion of arterial flow in the extremities at subsystolic pressures through the use of wide tourniquet cuffs.
FIGURE 4 – Noordin et al. (2009) Current Concepts Review – Surgical Tourniquets in Orthopaedics
While increasing from 10 to 20% AOP or 80-90% rAOP both significantly impacted blood flow, changing cuff pressure between 30 and 80% rAOP did not significantly impact SFA blood flow (30 vs. 80% rAOP: P=0.08; 40-70 vs. 80% rAOP: P=1.00). Thus, while blood flow may be trending towards a difference between 30% and 80% rAOP, the data convincingly illustrate that cuff pressures ranging from 40-80% rAOP elicit very similar blood flow responses at rest.
FIGURE 2 – Crossley et al. (2019) Effect of Cuff Pressure on Blood Flow during Blood Flow–restricted Rest and Exercise
Aerobic Fitness (Bike Tests) Module Explained – Read more
One Repetition Maximum (1RM) Module Explained – Read more
By the 1RM module you can estimate your one repetition maximum (1RM) with a submaximal load, or just enter your known 1RM, which is relevant for resistance training combined with BFR:
As a rule of thumb, for low pressure BFR Training i.e. 40-60% Limb Occlusion Pressure (LOP), we recommend to utilize “low-load resistance training” at about 30-45% of 1RM. For high pressure BFR training ie.60-80%, we recommend to use “very low-load” at about 15-30% of 1RM.
This One Rep Max module can be used to calculate weight (kg), reps and a percentage of 1RM for resistance training, which can be relevant to track progress or general exercise programming with or without the application of BFR.
Please mind, that just like the bike tests, RM testing should always be conducted after a proper and exercise specific warm-up without BFR.
As a rule of thumb, for safe and effective BFR augmented resistance training, you should aim for about 20-40% of your 1 RM calculated for each exercise individually.
In many cases it may not be appropriate to measure 1RM, e.g. after surgery, injury etc. In this case we recommend that you test the contra-lateral limb and use this data for exercising the effected limb.
Example 1: After knee surgery. Test and calculate the strength of the unaffected leg to calculate the corresponding 1RM and use this data in the app, to find an indicative load for your knee rehab.
In this case, please mind the associated strength loss in the effected limb. So, relative to time and severity of the surgery, aim for about 20% 1 RM with the recommended 30x15x15x15 rep protocol, and then progress either reps, pressure (mmHg) or load accordingly to the specific case.
Example 2: General fitness applications with BFR. For most individuals it is not feasible in regards to adherence, going to absolute failure. That is also why we recommend using a preset load and rep-scheme, then progress either load, weight, reps or pressure (mmHg) for the succeeding training session.
Calculate One-Repetition-Maximum (1RM) with a submaximal weight (Load) with the corresponding maximum Repetitions (Reps) or enter your known 1RM (Load) which equals 1 Rep.
Testing your 1RM requires a high degree of caution to avoid injury. We recommend to find the maximum weight (Load/kg) you can manage with a proper form for 5-10 Repetitions (Reps) after an appropriate exercise-specific warm-up in a non‐fatigued state.
Subsequently, you can use the sliders to set “% of 1RM”, “Reps” or “kg” relative to a percentage of your estimated 1RM.
Because of a significant intratester- and intertester variance in regards to different exercises and individuals, respectively, this calculation is only an estimation of 1RM, Reps and kg.
Remember to include about 75% of your bodyweight when applicable, e.g. back squat, split squat etc.
Example: Your current back squat is 100kg with a body weight of 80kg, use 100kg + 60kg = 160kg.
Epleys formula is currently used for the 1RM module: 1RM = Load * (1 + Reps / 30)
Source: Epley, B. Poundage chart. In: Boyd Epley Workout. Lincoln, NE: Body Enterprises, 2985. p. 86.