"Living Low - Training High" Methods and Physiological Responses in Well-trained Swimmers

Faculdade de Motricidade Humana

Status: Not yet enrolling

Conditions: Normobaric Hypoxia; Normoxia; Hypoventilation

Treatments: Other: Repeated sprint

Study type: Interventional

Funder types: Other

Identifiers

NCT06253039

RSH swimmers

Details and patient eligibility

About

To overcome the lack of knowledge regarding the impact of different "living low, training high" methods on swimming performance, a 4-week intervention will be carried out to determine and compare the effects of three Repeated Sprints in Hypoxia (RSH) methods with each other and with a control group. Our goal is to characterize and compare the adaptations in swimming performance and in cardiorespiratory, metabolic, and muscle oxygenation responses that can arise after a 4-week training period of RSH and RSH-voluntary hypoventilation (VHL) performed in a ski-ergometer.

Full description

Recently, several new "living low training high" (LLTH) methods involving repeated sprints in hypoxia have shown promising results, especially in team sports. However, the underlying mechanisms remain mostly unclear, as does its effectiveness in improving swimming performance.

Hypoxemia can be induced by exposure to ambient hypoxia conditions, by voluntary hypoventilation at low lung volume, or by vascular occlusion (namely, blood flow restriction). Swimming performance is influenced by aerobic and anaerobic metabolism and could benefit from these different LLTH methods.

This project aims to compare the effects of repeated sprint training performed with a ski-ergometer 1) in a hypoxic chamber and 2) with voluntary hypoventilation on the performance of swimmers, as well as to characterize cardiorespiratory, metabolic, and muscle oxygenation adaptations that may contribute to the improvements achieved after four weeks of each of these types of training.

All groups will be evaluated before and after the supervised training period in three testing sessions in normoxia, separated by at least 24 hours within 7 days. Swimmers will perform: 1) time-trial (100 m front crawl) in the swimming pool to determine performance, V̇̇O2 peak, and lactate concentration following the test; 2) incremental test to exhaustion in the swim-ergometer to determine aerobic peak power, cardiorespiratory responses (V̇̇O2max, ventilatory thresholds), and maximal tissue deoxygenation; 3) time-trial test in the ski-ergometer (100 m) to access performance, muscle and pulmonary oxygen uptake kinetics, and the relative contribution of energetic systems.

Training sessions will be performed in the ski-ergometer and consist of 4 sets of 5x6s all-out sprints with 24s and 5 min of passive rest between the sprints and sets, respectively. In all testing and training sessions, pulse oxygen saturation will be measured for safety purposes.

Enrollment: 36 estimated patients

Sex: All

Ages: 18 to 30 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Swimmers from both sexes;
• With regular participation in National Championships;
• More than five years of training experience;
• No recent exposure/acclimatization to altitude;
• No recent exposition to Blood Flow Restriction training.

Exclusion criteria

• athletes who had an acclimatization experience or exposure to altitude lasting more than 10 days in the last 6 months;
• pregnant or postpartum women;

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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36 participants in 3 patient groups

Normobaric hypoxia (RSH)

Experimental group

Description:

The RSH group will perform training sessions in a normobaric hypoxic chamber at a simulated altitude of 3000 meters (FiO2 14.5%)

Treatment:

Other: Repeated sprint

Hypoventilation (RSH-VHL)

Experimental group

Description:

RSH-VHL group will be asked to exhale down to functional residual capacity just before each repetition and then hold their breath until the end of the sprint

Treatment:

Other: Repeated sprint

Normoxia (RSN)

Active Comparator group

Description:

The control group will perform the training sessions in normoxia (FIO2, 20.9%)

Treatment:

Other: Repeated sprint