Comparison of Training Intensity Distribution Models in Recreational Distance Runners

Universidad Rey Juan Carlos

Status: Completed

Conditions: Running Performance; Exercise Physiology; Endurance Exercise

Treatments: Other: Polarided training intensity distribution; Other: Pyramidal Training Intensity Distribution; Other: Threshold Training Intensity Distribution

Study type: Interventional

Funder types: Other

Identifiers

NCT07565168

IND/22HUM-23661

IND/22HUM-23661-1

Details and patient eligibility

About

This study aims to compare the effects of three different training intensity distribution (TID) models-polarized, threshold, and pyramidal-on physiological and performance adaptations in recreational distance runners. Twenty-four participants will be assigned to one of the three training interventions and will complete an 8-week structured running program based on the respective TID approach.

The primary objective is to determine whether different TID models elicit distinct changes in key physiological markers and endurance performance. The study seeks to answer whether a specific intensity distribution strategy provides superior adaptations in recreational runners when training is prescribed over a controlled intervention period.

Full description

This study adopts a parallel-group experimental design to compare the effects of three training intensity distribution (TID) models-polarized, threshold, and pyramidal-on physiological and performance adaptations in recreational distance runners.

Eligible participants are required to be recreational runners with a minimum training frequency of four sessions per week. Following enrollment, all participants complete a one-week pre-intervention phase dedicated to baseline assessments and familiarization with testing procedures.

During this phase, participants will performe a comprehensive physiological evaluation to determine key endurance-related variables. These include ventilatory thresholds (e.g., VT1 and VT2), running economy, and maximal oxygen uptake (VO₂max), assessed through an incremental exercise test under standardized laboratory conditions. In addition, participants perform a 5-km time trial on a standardized course or controlled conditions to assess endurance performance.

Based on the physiological assessment, individual training intensities are prescribed using a five-zone intensity model derived from ventilatory thresholds and maximal aerobic capacity. This approach allows for precise classification of training load and ensures consistency in the application of the three TID models across participants.

Following baseline testing, participants are allocated to one of the three intervention groups (polarized, threshold, or pyramidal) and complete an 8-week structured endurance training program. Each training model differs in the relative distribution of time spent across the five intensity zones, while overall training frequency and general structure are maintained comparable between groups.

Training sessions are monitored using participants' GPS-enabled sport watches, which record variables such as duration, distance, pace, and heart rate. These data are used to quantify training load and verify adherence to the prescribed intensity distribution. Participants are instructed to follow the assigned training program and upload their training data regularly for supervision and compliance tracking.

At the end of the 8-week intervention, all baseline assessments are repeated under the same conditions. This includes the physiological testing to reassess ventilatory thresholds, running economy, and VO₂max, as well as the 5-km time trial to evaluate changes in endurance performance.

The primary aim of the study is to examine whether different TID models induce distinct adaptations in physiological determinants and performance outcomes when applied in a controlled, prospective training intervention in recreational runners.

Enrollment: 24 patients

Sex: All

Ages: 18 to 60 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• age ≥ 18 years;
• a habitual training frequency of ≥ 4 sessions·week
• running experience ≥ 2 years;
• absence of musculoskeletal injuries in the preceding 3 months

Exclusion criteria

• an official 10-km race time > 40:00 min:s for men and > 50:00 min:s for women
• any cardiometabolic disease

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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24 participants in 3 patient groups

Polarized training Intensity Distribution

Experimental group

Description:

Participants assigned to the polarized training group perform an 8-week structured endurance training program characterized by a high proportion of low-intensity exercise and a smaller proportion of high-intensity exercise, with minimal time spent at moderate intensities. Training intensity is prescribed using an individualized five-zone model based on baseline physiological assessments. The majority of training is performed in the lowest intensity zones (Zones 1-2), while high-intensity sessions are conducted in the highest zones (Zones 4-5). Training load and adherence are monitored using GPS-enabled sport watches.

Treatment:

Other: Polarided training intensity distribution

Threshold Training Intensity Distribution

Experimental group

Description:

Participants assigned to the threshold training group complete an 8-week structured endurance training program emphasizing a greater proportion of training at moderate-to-high intensities, particularly around the second ventilatory threshold. Training intensity is prescribed using an individualized five-zone model derived from baseline physiological assessments. A substantial portion of training is performed in intermediate zones (Zones 3-4), with comparatively less time spent at low (Zones 1-2) and high intensities (Zone 5). Training sessions are monitored via GPS-enabled sport watches to ensure adherence.

Treatment:

Other: Threshold Training Intensity Distribution

Pyramidal training Intensity Distribution

Experimental group

Description:

Participants assigned to the pyramidal training group perform an 8-week structured endurance training program characterized by a progressive decrease in training volume from low to high intensities. Training intensity is prescribed using an individualized five-zone model based on baseline physiological assessments. Most training is accumulated in low-intensity zones (Zones 1-2), with moderate amounts in intermediate zones (Zone 3) and smaller proportions at higher intensities (Zones 4-5), forming a pyramidal distribution. Training load and compliance are monitored using GPS-enabled sport watches.

Treatment:

Other: Pyramidal Training Intensity Distribution