As technological advancements continue to evolve, Human Activity Recognition (HAR) has emerged as a crucial area. This study aims to discern four human activities are sitting, standing, walking, and jogging while prioritizing user privacy by employing Elliptic Curve Cryptography (ECC) based blind signatures. The research focuses on predicting human activities through the Support Vector Machine (SVM) algorithm, utilizing data from accelerometer, gyroscope and Global Positioning System (GPS) sensors in smartphones. ECC, renowned for its shorter key length and faster processing, ensures data confidentiality. The SVM algorithm excels in categorizing human activities, achieving an impressive validation accuracy of around 99.16% with an average error of merely 3.33% in 30 real-time tests encompassing standing and walking. Notably, tests for sitting and running activities showed no errors. Moreover, the system's practicality is evident as the classification process requires only 1 ms. ECC's blind signature implementation effectively upholds user anonymity, fulfilling crucial criteria such as confidentiality, correctness, integrity, non-repudiation, blindness, unforgeability, and untraceability, without imposing substantial computational costs.