Normobaric Hypoxia as a Strength Training Intensity Amplifier in Ice Hockey Players: Effects on Anaerobic Performance and Muscle Contraction Properties

Condition(s) studied

Investigational drug(s) / intervention(s)

Resistance Training (High-Intensity): Leg press exercise performed at 70-80% of 1RM, structured as 4 sets × 10 repetitions, with controlled tempo and standardized rest intervals (2 minutes).

Resistance Training (Low-Intensity): Leg press exercise performed at 20-30% of 1RM, structured as 4 sets (30/15/15/15 repetitions), with controlled tempo and shorter rest intervals (1 minute).

Normobaric Hypoxia: Environmental intervention simulating an altitude of approximately 3500 meters (\~13.5% FiO₂) using a normobaric hypoxic chamber.

Normoxia: Training under normal atmospheric oxygen conditions (\~20.9% FiO₂).

Study summary

The goal of this research study is to investigate the effects of resistance training performed under normobaric hypoxia (simulated altitude conditions) on anaerobic performance, lactate clearance, and muscle contractility in elite ice hockey players. The main questions it aims to answer are:

Does resistance training under hypoxic conditions improve anaerobic peak power and mean power compared to training under normal oxygen conditions?

Does training under hypoxia affect lactate kinetics and buffering capacity differently than normoxic training?

Does hypoxic training enhance muscle contractility properties differently compared to normoxic training?

In practice: Can hypoxic training help injured athletes maintain performance levels while reducing overall physical stress and preventing detraining?

Researchers will compare four training approaches:

High-intensity training in normoxia (normal oxygen conditions)

Low-intensity training in normoxia

High-intensity training in hypoxia (simulated altitude of 3500 meters)

Low-intensity training in hypoxia

Participants will:

Perform resistance training sessions using a leg press twice a week for 6 weeks, with progressively increased intensity.

Complete anaerobic performance tests (Wingate tests for both lower and upper limbs) before and after the training intervention.

Undergo tensiomyographic assessments to evaluate muscle contractility.

Provide capillary blood samples at 0, 4, and 8 minutes post-exercise to assess lactate clearance and metabolic recovery.

Eligibility

Primary outcome measure(s)

• Anaerobic Performance (2x Wingate Test) — Baseline (pre-intervention) and 6 weeks (immediately post-intervention)
  Change in anaerobic performance will be assessed using peak power (W) and mean power output (W), determined through the Wingate Anaerobic Test performed on a cycle ergometer. Lower-limb anaerobic performance will be evaluated by two consecutive Wingate tests, separated by a 20-minute rest period, to ensure reliability. An additional Wingate test for the upper limbs serves as an internal control.
• Lactate Clearance Kinetics — Baseline (pre-intervention) and 6 weeks (post-intervention)
  Capillary blood lactate concentrations will be assessed at baseline (0 min immediately post-exercise), and at 4 and 8 minutes post-exercise, to evaluate lactate production and clearance kinetics following maximal anaerobic efforts.
• Muscle Contractility (Tensiomyography) — Time Frame: Baseline (pre-intervention) and 6 weeks (post-intervention)
  Muscle contractile properties (contraction time-Tc, and maximal radial displacement-Dm) will be assessed via tensiomyography (TMG) on the vastus lateralis muscle (trained muscle group) and triceps brachii (untrained control muscle), to evaluate neuromuscular adaptations following the intervention.

Trial sites (1)

More The Jerzy Kukuczka Academy of Physical Education in Katowice trials in Poland