Effects of Two Endurance Training Programs on 5-km Running Performance in Recreational Runners

Effects of Lactate Threshold Training and Pyramidal-to-Polarized Endurance Training on 5-km Running Performance, Physiological Capacity, and Post-exercise Neural Responses in Recreational Runners: A Randomized Controlled Trial

This study will examine the effects of two 8-week endurance training programs on 5-km running performance in recreational runners. Participants will be randomly assigned to a lactate threshold training group, a pyramidal-to-polarized endurance training group, or a control group that maintains usual physical activity without receiving the study training program.

Before and after the intervention, participants will complete assessments of 5-km running performance, aerobic fitness, lactate threshold, running economy, blood lactate responses, and brain activity recorded before and after maximal exercise. The study will compare changes among the three groups and examine whether physiological and post-exercise neural responses are associated with improvements in running performance.

The main purpose is to determine whether the two training programs produce different improvements in 5-km running performance and to better understand the physiological and neural adaptations associated with endurance training in recreational runners.

Study Overview

• Status: Not yet recruiting
• Conditions: Exercise Training Adaptation; Endurance Running Performance
• Intervention / Treatment: Behavioral: Lactate Threshold Training; Behavioral: Pyramidal-to-Polarized Endurance Training

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Shuqi Jia; Phone Number: +8613327732991; Email: jsq2221111006@163.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Men and women aged [18-30] years.
• Recreational runners with regular running or endurance-training experience for at least [6 months].
• Currently completing running training at least [2-3 times per week].
• Able to complete a continuous 5-km run.
• Willing and able to complete the 8-week training intervention and all study assessments.
• Able to understand the study procedures and provide written informed consent.

Exclusion Criteria:

• Current cardiovascular, respiratory, metabolic, neurological, or other medical conditions that may contraindicate maximal exercise or endurance training.
• Current musculoskeletal injury or pain that limits running or participation in maximal exercise testing.
• History of loss of consciousness, epilepsy, severe head injury, or other neurological conditions that may affect electroencephalographic recordings.
• Use of medications or substances known to substantially affect cardiovascular, metabolic, or central nervous system responses to exercise.
• Participation in another structured exercise intervention or clinical study during the study period.
• Inability or unwillingness to comply with the assigned training program, testing procedures, or study requirements.
• Any other condition judged by the investigators to make participation unsafe or to substantially affect the validity of the study outcomes.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Lactate Threshold Training Group; Participants assigned to this group will complete an 8-week endurance training program primarily prescribed around their individually determined lactate threshold intensity. Training intensity will be individualized using baseline physiological testing and adjusted according to the study protocol. Participants will complete the prescribed training sessions throughout the intervention period and will undergo the same pre- and post-intervention assessments as the other study groups.	Behavioral: Lactate Threshold Training; Participants will complete an 8-week individualized endurance training program prescribed primarily around the lactate threshold. Training intensity will be determined from baseline physiological testing. The program will specify the frequency, duration, and intensity of each training session and will be adjusted according to the study protocol.
Experimental: Pyramidal-to-Polarized Endurance Training Group; Participants assigned to this group will complete an 8-week periodized endurance training program in which the training-intensity distribution progresses from a pyramidal pattern during the initial phase to a polarized pattern during the later phase. Exercise intensity will be individualized using baseline physiological testing and adjusted according to the study protocol. Participants will undergo the same pre- and post-intervention assessments as the other study groups.	Behavioral: Pyramidal-to-Polarized Endurance Training; Participants will complete an 8-week individualized endurance training program in which the training-intensity distribution progresses from a pyramidal pattern during the initial phase to a polarized pattern during the later phase. Training intensity will be prescribed using individually determined physiological thresholds obtained from baseline testing. The program will include low-, moderate-, and high-intensity running sessions, with the relative distribution of training time across intensity zones adjusted according to the planned periodization. Training frequency, session duration, and intensity will be standardized according to the study protocol and monitored throughout the intervention.
No Intervention: Usual Activity Control Group; Participants assigned to this group will continue their usual physical activity and running habits during the 8-week study period and will not receive either of the structured training programs administered by the research team. Participants will be asked not to begin any new structured endurance training program during the intervention period and will undergo the same pre- and post-intervention assessments as the training groups.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in 5-km Running Performance	5-km running performance will be assessed using a maximal-effort self-paced 5-km run conducted on a standard 400-m outdoor athletics track. Completion time will be recorded in seconds. The primary outcome will be the change in 5-km completion time from baseline to the end of the 8-week intervention. A lower completion time indicates better running performance.	Baseline and immediately after the 8-week intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Maximal Oxygen Uptake	Maximal oxygen uptake will be assessed during a graded cardiopulmonary exercise test performed to volitional exhaustion. Oxygen uptake will be measured breath-by-breath and expressed relative to body mass in milliliters per kilogram per minute. The outcome will be the change in maximal oxygen uptake from baseline to the end of the 8-week intervention.	Baseline and immediately after the 8-week intervention
Change in Lactate Threshold	Lactate threshold will be determined during an incremental running test using blood lactate measurements and the prespecified threshold-identification method described in the study protocol. The outcome will be the change in running speed or physiological intensity corresponding to the lactate threshold from baseline to the end of the 8-week intervention.	Baseline and immediately after the 8-week intervention
Change in Running Economy	Running economy will be assessed during steady-state submaximal treadmill running at a standardized speed. Oxygen uptake will be measured during the steady-state period and expressed relative to body mass. The outcome will be the change in oxygen cost of running from baseline to the end of the 8-week intervention. A lower oxygen cost at the same running speed indicates better running economy.	Baseline and immediately after the 8-week intervention
Change in Post-exercise Blood Lactate Concentration	Capillary blood lactate concentration will be measured at prespecified time points before and after maximal exercise. The outcome will include changes in post-exercise blood lactate concentration and lactate recovery from baseline to the end of the 8-week intervention. Blood lactate concentration will be expressed in millimoles per liter.	Baseline and immediately after the 8-week intervention, with measurements before exercise and at 5 and 20 minutes after exercise
Change in Post-exercise Electroencephalographic Activity	Resting electroencephalographic activity will be recorded before maximal exercise and during recovery after exercise. Prespecified electroencephalographic outcomes will include relative spectral power in selected frequency bands and cortical regions. The outcome will be the change in post-exercise electroencephalographic responses from baseline to the end of the 8-week intervention.	Baseline and immediately after the 8-week intervention, with electroencephalographic recordings before exercise and at 5 and 20 minutes after exercise

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Event-Related Potential Responses During Cognitive Tasks	Event-related potentials will be recorded during prespecified cognitive tasks before and after the 8-week intervention. Prespecified outcomes will include the amplitude and latency of selected ERP components, including N2 and P3 components, at predefined scalp regions and task conditions. The outcome will be the change in ERP amplitude and latency from baseline to the end of the intervention, as well as changes in the acute ERP response from before to after maximal exercise.	Baseline and immediately after the 8-week intervention, with recordings before exercise and at 5 and 20 minutes after maximal exercise

Collaborators and Investigators

• Sponsor: Shuqi Jia

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2026
• Primary Completion (Estimated): October 1, 2026
• Study Completion (Estimated): November 8, 2026

Study Registration Dates

• First Submitted: July 28, 2026
• First Submitted That Met QC Criteria: July 28, 2026
• First Posted (Actual): July 31, 2026

Study Record Updates

• Last Update Posted (Actual): August 3, 2026
• Last Update Submitted That Met QC Criteria: July 30, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Endurance Training; 5-km Running Performance; Pyramidal Training; Running Economy; Polarized Training; Recreational Runners
• Other Study ID Numbers: SUS-5KM-RCT-2026

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared because the current informed consent and ethics-approved study documents do not include provisions for external sharing of participant-level data. Aggregate results may be reported in publications.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No