Interval walking training
From Wikipedia, the free encyclopedia
Interval walking training (IWT), also known as Japanese walking or Nihon Aruki, is a structured aerobic exercise method that alternates between slow and fast walking in set intervals for a minimum of 30 minutes per session. The method was developed by exercise physiologists Hiroshi Nose and Shizue Masuki at Shinshu University Graduate School of Medicine in Matsumoto, Nagano, Japan, and first described in scientific literature in 2007.[1] Unlike regular steady-paced walking, IWT applies the principles of high-intensity interval training (HIIT), making it accessible to a wide range of ages and fitness levels without specialized equipment or a gym environment.[2]
History
The concept of IWT emerged from research conducted at Shinshu University in Matsumoto, Japan, during the early 2000s. Professor Hiroshi Nose and Associate Professor Shizue Masuki, both of the Graduate School of Medicine's Department of Sports Medical Sciences, aimed to develop an exercise program that would improve cardiovascular and metabolic health in middle-aged and older adults.[2] The researchers based their approach on interval training used by competitive endurance athletes, adapting that structure to the low-impact format of walking so that it could be performed freely in everyday environments without constant professional supervision.[3]
The foundational clinical study was published in 2007 in Mayo Clinic Proceedings.[1] The method was subsequently introduced to the public in Japan as part of a health promotion programme called the Jukunen Taiikydaigaku Program, aimed at improving fitness in adults over 40 without the physical strain of high-impact workouts.[4]
IWT is sometimes mistaken with the 10,000 steps per day method, which originated in Japan during the 1960s as a commercial pedometer marketing campaign. Nose and Masuki have explicitly separated IWT from that goal, emphasising that their method is defined by exercise intensity rather than total step volume.[4] From the mid-2010s, IWT has received broader international attention, with researchers in Denmark adapting the protocol for clinical use in type 2 diabetes and developing a smartphone application called InterWalk to deliver the training at scale without requiring a personal trainer.[5]
Method
The IWT protocol consists of repeated 3-minute intervals alternating between high- and low-intensity walking. During the high-intensity phase, participants walk at a pace above 70% of their individual peak aerobic capacity, then drop to the low-intensity phase at around 40% for the following 3 minutes. They repeat this cycle at least 5 times, giving a total session of 30 minutes or more, and aim to do this four or more times per week.[1][6]
The characteristic of IWT is the individualization of its intensity targets. Rather than prescribing a fixed walking speed or heart rate, the protocol developed fast and slow phases tailored to each participant's aerobic capacity. This means that two individuals with different fitness levels can follow the same protocol at very different speeds, yet both are working at the appropriate intensity for their bodies. In practical terms, the fast phase should feel challenging enough to make maintaining the protocol difficult, while the slow phase allows partial recovery without reaching complete rest.[7]
Scientific research
The foundational 2007 study by Nose and Masuki enrolled 246 participants (60 men, 186 women; average age 63) divided into three groups and reported improvements in aerobic capacity, muscle strength, and blood pressure.[1] Follow-up research published in 2009 found that five months of training improved physical fitness and lifestyle-related disease indices by 10–20%.[8]