Local and Systemic Oxygen Saturation During 'Death by Squats' Exercise

Analysis of Local and Systemic Oxygen Saturation During Monotonous Exercise Using the Example of 'Death by Squats'

During the exercise intervention "Death by Squats", which compasses body weight squats until maximum exertion, 25-30 subjects shall be tested for heart rate, the oxygen saturation of the vastus medialis and the triceps, resting and at maximum exertion blood lactate, as well as the rate of perceived exertion on the borg scale. At the end, all should indicate their primary reason for stopping (local fatigue, systemic fatigue, time constraints, motivational deficit).

Study Overview

• Status: Recruiting
• Conditions: Fatigue; Oxygen Saturation; Quadriceps Muscle; Anaerobic Threshold
• Intervention / Treatment: Diagnostic test: Death by Airsquat

Detailed Description

Subjects in this study will be measured while they are engaged in an exercise protocol until maximum exertion, each in groups of three persons. The overall duration of the study is planned from April 2023 (start of recruitment) until December 2024 (finalization of data acquisition and analysis).

Subjects are executing a CrossFit workout which is planned as follows: Every minute, participants have to perform a given number of Airsquats (bodyweight squat). The first minute starts off with 10 repetitions, the remaining time can be used as a break. In minute two, 12 repetitions have to be done, in minute three 14 repetition, and so on. The subjects stick to this protocol until maximum exertion, in other words, until they are no longer able to execute the given repetitions within the actual minute. During the workout, heart rate is tracked by a 'Polar' chest strap, and the oxygen saturation of the vastus medialis and the triceps are measured using the 'Moxy' muscle oxygen monitor. Further, at rest and at maximum exertion, a blood lactate sample is taken (EKF lactate scout). Subjects rate their perceived exertion on the borg scale after quitting and indicate their primary reason for stopping (local fatigue in legs, systemic fatigue, time constraints).

• Study Type: Observational
• Enrollment (Estimated): 100

Contacts and Locations

• Study Contact: Name: Annette Schmidt, Prof; Phone Number: +49 89 6004 4412; Email: annette.schmidt@unibw.de
• Study Contact Backup: Name: Jennifer Schlie, M.Sc.; Phone Number: +49 89 6004 4774; Email: jennifer.schlie@unibw.de

Study Locations

• Germany
  • Bayern
    • Munich, Bayern, Germany, 85577
      • Recruiting
      • University of the Bundeswehr Munich
      • Contact: Petra Neudorfer; Phone Number: +49 89 6004 4181; Email: petra.neudorfer@unibw.de

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Male and female participants of 18 years and older, that are performing a CrossFit class with the EMOM workout "Death by Airsquat".

Description

Inclusion Criteria:

• being moderately to severely physically active al least 2 hours/week (all types of sport are eligible)

Exclusion Criteria:

• akute infections, musculoskeletal injuries
• chronic cardiovascular or pulmonary diseases (in case of uncertainty, we recommend appraisal from medical personnel)

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Death by Airsquat Exercise; All participants follow the exercise protocol, based on the "every minute on the minute" principle: Starting off with 10 body weight squats in the first minute (after completion, the remaining seconds can be always be used as a break). In minute two, 12 squats have to be completed. In minute three, 14 squats, and so forth. Until maximum exertion is reached and/or until the number of squats within 60 seconds can not be increased further. Every individual stops at his/her performance limit

Diagnostic test: Death by Airsquat; Increasing number of squats have to be completed every minute (EMOM principle).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Local and systemic SmO2 curve	From the start of the exercise intervention until individual exhaustion (expected between 15 to 30 minutes), with SmO₂ continuously recorded during exercise and final measurement taken immediately upon exhaustion.

Secondary Outcome Measures

Outcome Measure	Time Frame
Type of sports practiced	Questionnaire administered within 5 minutes after test completion to assess type of sports practiced.

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Anthropometric parameters will be assessed	The following anthropometric parameters will be assessed: body mass (kg); body height (cm); BMI (kg/m², calculated from body mass and height); limb circumference (cm); skinfold thickness (mm)	Anthropometric measurements will be taken immediately after the completion of the exercise intervention (expected between 15 to 30 minutes after the start of exercise).
Blood lactate concentration at rest and post-exercise		At rest (prior to exercise) and immediately upon individual exhaustion (expected between 15 to 30 minutes after the start of exercise). Additional post-exercise measurements at 2, 5, and 10 minutes if applicable.

Collaborators and Investigators

• Sponsor: Bundeswehr University Munich

Study record dates

Study Major Dates

• Study Start (Actual): February 8, 2025
• Primary Completion (Estimated): December 1, 2025
• Study Completion (Estimated): December 1, 2025

Study Registration Dates

• First Submitted: February 8, 2025
• First Submitted That Met QC Criteria: March 18, 2025
• First Posted (Actual): March 25, 2025

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: March 18, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Fatigue
• Other Study ID Numbers: DBS23

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes